diff --git a/site/src/components/RelatedBooks.astro b/site/src/components/RelatedBooks.astro
new file mode 100644
index 0000000..f24ec61
--- /dev/null
+++ b/site/src/components/RelatedBooks.astro
@@ -0,0 +1,70 @@
+---
+import { Badge } from '@/components/ui/badge';
+import type { CollectionEntry } from 'astro:content';
+
+interface RelatedBookResult {
+  book: CollectionEntry<'books'>;
+  sharedTopics: string[];
+  overlapCount: number;
+}
+
+interface Props {
+  relatedBooks: RelatedBookResult[];
+  currentCollection: string;
+}
+
+const { relatedBooks, currentCollection } = Astro.props;
+---
+
+{relatedBooks.length > 0 && (
+  <section class="space-y-4">
+    <h2 class="text-lg font-semibold title-accent text-foreground">Related Notebooks</h2>
+    <div class="grid grid-cols-2 md:grid-cols-4 gap-4">
+      {relatedBooks.map(({ book, sharedTopics }) => {
+        const slug = book.slug.split('/').pop();
+        const isCrossCollection = book.data.collection !== currentCollection;
+        return (
+          <a
+            href={`/${book.data.collection}/${slug}`}
+            class="book-card block bg-card rounded-lg border border-border overflow-hidden hover:border-primary/50"
+          >
+            <div class="relative">
+              {book.data.coverImage ? (
+                <img
+                  src={book.data.coverImage}
+                  alt={`Cover of ${book.data.shortTitle}`}
+                  class="w-full aspect-[3/4] object-cover object-top"
+                  loading="lazy"
+                />
+              ) : (
+                <div class="w-full aspect-[3/4] bg-muted flex items-center justify-center">
+                  <svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round" class="text-muted-foreground">
+                    <path d="M2 3h6a4 4 0 0 1 4 4v14a3 3 0 0 0-3-3H2z"/>
+                    <path d="M22 3h-6a4 4 0 0 0-4 4v14a3 3 0 0 1 3-3h7z"/>
+                  </svg>
+                </div>
+              )}
+              {isCrossCollection && (
+                <div class="absolute top-2 left-2 bg-card/90 backdrop-blur-sm text-[10px] font-medium px-1.5 py-0.5 rounded border border-border">
+                  {book.data.collection === 'mims' ? 'Mims' : "Ugly's"}
+                </div>
+              )}
+            </div>
+            <div class="p-3 space-y-2">
+              <h3 class="text-sm font-semibold text-foreground title-accent line-clamp-2 leading-tight">
+                {book.data.shortTitle}
+              </h3>
+              <div class="flex flex-wrap gap-1">
+                {sharedTopics.slice(0, 2).map((topic) => (
+                  <Badge variant="secondary" className="text-[10px]">
+                    {topic.replace(/-/g, ' ')}
+                  </Badge>
+                ))}
+              </div>
+            </div>
+          </a>
+        );
+      })}
+    </div>
+  </section>
+)}
diff --git a/site/src/lib/related-books.ts b/site/src/lib/related-books.ts
new file mode 100644
index 0000000..2c16247
--- /dev/null
+++ b/site/src/lib/related-books.ts
@@ -0,0 +1,45 @@
+import type { CollectionEntry } from 'astro:content';
+
+interface RelatedBookResult {
+  book: CollectionEntry<'books'>;
+  sharedTopics: string[];
+  overlapCount: number;
+}
+
+function normalizeTopic(topic: string): string {
+  return topic.toLowerCase().replace(/[\s_]+/g, '-');
+}
+
+export function getRelatedBooks(
+  currentBook: CollectionEntry<'books'>,
+  allBooks: CollectionEntry<'books'>[],
+  maxResults = 4
+): RelatedBookResult[] {
+  const currentTopics = new Set(currentBook.data.topics.map(normalizeTopic));
+
+  return allBooks
+    .filter((b) => b.slug !== currentBook.slug)
+    .map((book) => {
+      const bookTopics = new Set(book.data.topics.map(normalizeTopic));
+      const sharedTopics = [...currentTopics].filter((t) => bookTopics.has(t));
+      const union = new Set([...currentTopics, ...bookTopics]);
+      const jaccard = union.size > 0 ? sharedTopics.length / union.size : 0;
+
+      return {
+        book,
+        sharedTopics: sharedTopics.map((t) =>
+          book.data.topics.find((orig) => normalizeTopic(orig) === t) || t
+        ),
+        overlapCount: sharedTopics.length,
+        jaccard,
+      };
+    })
+    .filter((r) => r.overlapCount > 0)
+    .sort((a, b) => {
+      if (b.overlapCount !== a.overlapCount) return b.overlapCount - a.overlapCount;
+      if (b.jaccard !== a.jaccard) return b.jaccard - a.jaccard;
+      return a.book.data.sortOrder - b.book.data.sortOrder;
+    })
+    .slice(0, maxResults)
+    .map(({ book, sharedTopics, overlapCount }) => ({ book, sharedTopics, overlapCount }));
+}
diff --git a/site/src/pages/mims/[slug].astro b/site/src/pages/mims/[slug].astro
index 3a5ae76..d236f0b 100644
--- a/site/src/pages/mims/[slug].astro
+++ b/site/src/pages/mims/[slug].astro
@@ -3,6 +3,8 @@ import Layout from '@/layouts/Layout.astro';
 import { Badge } from '@/components/ui/badge';
 import EBookReader from '@/components/EBookReader';
 import { getCollection, type CollectionEntry } from 'astro:content';
+import { getRelatedBooks } from '@/lib/related-books';
+import RelatedBooks from '@/components/RelatedBooks.astro';
 
 export async function getStaticPaths() {
   const books = await getCollection('books');
@@ -30,6 +32,7 @@ const mimsBooks = allBooks
 const currentIndex = mimsBooks.findIndex(b => b.slug === book.slug);
 const prevBook = currentIndex > 0 ? mimsBooks[currentIndex - 1] : null;
 const nextBook = currentIndex < mimsBooks.length - 1 ? mimsBooks[currentIndex + 1] : null;
+const relatedBooks = getRelatedBooks(book, allBooks);
 ---
 
 <Layout title={shortTitle} description={description}>
@@ -68,16 +71,13 @@ const nextBook = currentIndex < mimsBooks.length - 1 ? mimsBooks[currentIndex +
         </div>
 
         <div class="flex flex-wrap gap-2">
-          {topics.slice(0, 5).map((topic) => (
-            <Badge variant="secondary" className="text-xs">
-              {topic.replace(/-/g, ' ')}
-            </Badge>
+          {topics.map((topic) => (
+            <a href={`/mims?topics=${topic}`}>
+              <Badge variant="secondary" className="text-xs hover:bg-primary hover:text-primary-foreground transition-colors">
+                {topic.replace(/-/g, ' ')}
+              </Badge>
+            </a>
           ))}
-          {topics.length > 5 && (
-            <Badge variant="outline" className="text-xs">
-              +{topics.length - 5} more
-            </Badge>
-          )}
         </div>
       </div>
 
@@ -124,6 +124,9 @@ const nextBook = currentIndex < mimsBooks.length - 1 ? mimsBooks[currentIndex +
       />
     </div>
 
+    <!-- Related Books -->
+    <RelatedBooks relatedBooks={relatedBooks} currentCollection="mims" />
+
     <!-- Navigation -->
     <div class="flex items-center justify-between pt-8 border-t border-border">
       {prevBook ? (
diff --git a/site/src/pages/uglys/[slug].astro b/site/src/pages/uglys/[slug].astro
index 7f8f14e..3472035 100644
--- a/site/src/pages/uglys/[slug].astro
+++ b/site/src/pages/uglys/[slug].astro
@@ -3,6 +3,8 @@ import Layout from '@/layouts/Layout.astro';
 import { Badge } from '@/components/ui/badge';
 import EBookReader from '@/components/EBookReader';
 import { getCollection, type CollectionEntry } from 'astro:content';
+import { getRelatedBooks } from '@/lib/related-books';
+import RelatedBooks from '@/components/RelatedBooks.astro';
 
 export async function getStaticPaths() {
   const books = await getCollection('books');
@@ -30,6 +32,7 @@ const uglysBooks = allBooks
 const currentIndex = uglysBooks.findIndex(b => b.slug === book.slug);
 const prevBook = currentIndex > 0 ? uglysBooks[currentIndex - 1] : null;
 const nextBook = currentIndex < uglysBooks.length - 1 ? uglysBooks[currentIndex + 1] : null;
+const relatedBooks = getRelatedBooks(book, allBooks);
 ---
 
 <Layout title={shortTitle} description={description}>
@@ -68,16 +71,13 @@ const nextBook = currentIndex < uglysBooks.length - 1 ? uglysBooks[currentIndex
         </div>
 
         <div class="flex flex-wrap gap-2">
-          {topics.slice(0, 5).map((topic) => (
-            <Badge variant="secondary" className="text-xs">
-              {topic.replace(/-/g, ' ')}
-            </Badge>
+          {topics.map((topic) => (
+            <a href={`/uglys?topics=${topic}`}>
+              <Badge variant="secondary" className="text-xs hover:bg-primary hover:text-primary-foreground transition-colors">
+                {topic.replace(/-/g, ' ')}
+              </Badge>
+            </a>
           ))}
-          {topics.length > 5 && (
-            <Badge variant="outline" className="text-xs">
-              +{topics.length - 5} more
-            </Badge>
-          )}
         </div>
       </div>
 
@@ -124,6 +124,9 @@ const nextBook = currentIndex < uglysBooks.length - 1 ? uglysBooks[currentIndex
       />
     </div>
 
+    <!-- Related Books -->
+    <RelatedBooks relatedBooks={relatedBooks} currentCollection="uglys" />
+
     <!-- Navigation -->
     <div class="flex items-center justify-between pt-8 border-t border-border">
       {prevBook ? (