diff --git a/collects/meta/props b/collects/meta/props
index c45f008b13..7df417cc59 100755
--- a/collects/meta/props
+++ b/collects/meta/props
@@ -1900,6 +1900,7 @@ path/s is either such a string or a list of them.
 "collects/tests/xml" responsible (jay)
 "collects/tests/xml/test-clark.rkt" drdr:command-line #f drdr:timeout 300
 "collects/tests/xml/xml-snip-bug.rkt" drdr:command-line (gracket "-t" *)
+"collects/tests/zo-size.rkt" responsible (jay)
 "collects/tex2page" responsible (jay)
 "collects/texpict" responsible (mflatt robby)
 "collects/texpict/balloon.rkt" drdr:command-line (gracket-text "-t" *)
diff --git a/collects/tests/zo-size.rkt b/collects/tests/zo-size.rkt
new file mode 100644
index 0000000000..953d62d2b8
--- /dev/null
+++ b/collects/tests/zo-size.rkt
@@ -0,0 +1,29 @@
+#lang racket/base
+(require racket/path
+         racket/match)
+
+(define (indent i)
+  (for ([t (in-range i)])
+    (printf "|")))
+
+(define (dir-zo-size i p)
+  (parameterize ([current-directory p])
+    (define subdir? #f)
+    (define (has-sub-dir!)
+      (unless subdir?
+        (indent i) (printf "~a:\n" p)
+        (set! subdir? #t)))
+    (define tot
+      (for/fold ([size 0])
+        ([p (in-list (directory-list))])
+        (+
+         (match p
+           [(? directory-exists?) (has-sub-dir!) (dir-zo-size (add1 i) p)]
+           [(app filename-extension #"zo") (file-size p)]
+           [else 0])
+         size)))
+    (unless (zero? tot)
+      (indent i) (printf "~a: ~a\n" p tot))
+    tot))
+
+(void (dir-zo-size 0 (simplify-path (build-path (collection-path "racket") 'up))))
\ No newline at end of file