General:
Adobe
Computer Maintenance:
AdAware-anti-spyware
Spybot-anti-spyware
Fonts:
Dafont.com-lots of cool fonts.
Absolute Fonts Archive-lots of fonts, and you can make buttons and logos-even upload your own texture or font for them.
Image and Photo:
The GIMP-free image and photo studio similar to photoshop.
Photo Filtre-also free, like a lighter version of GIMP and easier to use.
Game:
