The best thing about free is...well it's free. I'm still a die-hard Mac fan so I had to post this. When I find one for PCs I'll post it. As one commentator pointed out, this list was compiled awhile ago.
I think AppFresh was on the last image. It's a great way to keep up on the most recent updates available for apps, widgets, and plugins. Be careful though, a few glitches you may encounter when:
-the update requires an OS update i.e. Leopard to Snow Leopard
-the update requires a new license the District doesn't own
-the app goes from freeware to shareware