Some good things:

• Trac – A blog, Subversion repository viewer, and project management system in one easy-to-swally capsule. Gorgeous diff display too 🙂
• Synergy – share a mouse and keyboard with multiple machines, all running different operating systems with no hardware. And it’s free!
• csoap – SOAP in pure C with http client and server.
• The last 30 picture uploads on livejournal – all human life, in pictures. A good way to kill those spare minutes/hours/years. Click and reload to lose your spare time.

Thanks to Nik for the first 2.