Paint.Net

This is more of a post than a tutorial. I just found out aboout paint.NET a paint program, and think it's great. It has tons of support and easy to use interface, plus tons of downloadable add-ons. It's quick and fun to use.
Advantages: Good for Second Life Textures, good support and add-ons, it's an alternitive to photoshop.
Disadvantages: Only for windows :(
Here is a screen shot of the interface.

Just usualy not so squished.
My rating is 9.0 out of 10.0
You can get it here. Scroll down to bottom of the page.