8 I've been using Gimp for years now for all my image manipulation needs. If you're an experienced Photoshop user you might find it a bit confusing at first, but there is a slightly modified version of it called GimpShop, which should make the transition easier.
In my opinion it's a good substitute for commercial applications, unless you're a DTP or graphics professional with more advanced needs.

10 Apart from being a highly extensible IDE for various programming languages (Java, C, Python, PHP, etc.), Eclipse is also a great runtime framework for building rich desktop applications.