MacOSaiX lets you build mosaic images from various photo libraries, including your, google images or videos. It's been in alpha state for ages, but glad to see it's finally updated and Leopard compatable.

Version: 2.0
Released: Nov. 19, 2007
New features:
Now compatible with Leopard.
Newly found images now "zoom" into place.
Image sources can now be designated as "filler".
Saving mosaics as very large images is now handled more gracefully.
Handling of EPS images is improved.
Bugs Fixed:
Folder image sources no longer reset when a mosaic project is re-opened.
Symbolic links are now handled correctly by Folder image sources.
Searching for flickr photos that match all of the given tags now works correctly.
Google images sources are working again when running on Mac OS X 10.3 (Panther).
Google images sources now load correctly when a mosaic project is re-opened.
QuickTime image sources now behave better.
No longer crashing when using red-, green- or bluescale colors with a Glyphs image source.
No longer crashing when getting the count of matching photos from flickr.
No longer crashing when an invalid image is chosen as the original.
No longer crashing when double-clicking the hand-picked image source.
No longer crashing at some point after editing an image source.
No longer crashing on quit when there is an unsaved Glyphs image source.
No longer crashing when clicking in the menu bar when no windows are open.
Many memory leaks were fixed.
Known issues:
Hiding the status bar is not working.
Zooming the window causes it to jump around.