1. Plexus puzzle: http://www.smart-kit.com/games/jigsaw/
2. URL-changing puzzles: http://www.lazylaces.com/article.asp?p=3140
3. Music using only the sounds from Windows 98 and XP:
http://www.youtube.com/watch?v=dsU3B0W3TMs
4. Goggles, the Google Maps flight sim: http://www.isoma.net/games/goggles.html
5. Falling Sand: http://chir.ag/stuff/sand/
And one called the Desktop Wallpaper Project .. creative and unique wallpaper by new artists, showcased on one site:
http://kitsunenoir.com/blog/2008/03/05/the-desktop-wallpaper-project/
(Credit for sites: Dark Roasted Blend, Didn't You Hear, Deputy Dog, Thinkorthwim)

