Here's my exercises for graphic design with Photoshop and Illustrator. Some are from tutorials, mostly Andrei Marius and Andrew Rosek.

Campass
Icecream
Enterprise
TIE Fight
Soda the Cat
Zeppelin
Chinstrap Penguin
Spidey
Blizzard
Cheese Riot
Imitation of Apple Wallpaper
Carpet from Shinning
Spinning
Marine Wallpaper
Avocado Wallpaper
Hexagon
Smoke
Smoke
Self Trace