You can check out Photofiltre from http://www.photofiltre.com/
I just downloaded a trial and had a play (i was looking for easy software for my son to have a got at - i use photoshop but its a bit tricky for him). Anyway -its really good! It has layers, loads of filters, drop shadows, lasso tools etc. Plus its pretty easy to use. I did a search on here and maybe people havent come across it much before.
But the most exciting thing is that i've discovered that you can make your own full colour 'brushes'. Cool...
I've put a post up about it on my blog
, and a freebie 'Nozzle' set. Theyre like full colour brush stamps. These ones are low res, but if people liked them I will probably make more sets.
Anyway.. tis late and i ramble.. just thought i'd share!
ps. Im nothing to do with the makers of the software by the way. Just wanted a way to make full colour 'robot stamps' for my boy!