Program for making simple thumbnails


Posting Mad!
hey guys what are some good programs that are easy to use and make simple yet sleek thumbnails on a Macbook and also a PC.
I use Pixelmator - it's in the App Store. Not free, but I find it easily comparable to photoshop at a fraction of the price!
I usually make my thumbnails right in After Effects after I finish a video. But realistically pretty much any program
Photoshop Portable CS4 is pretty good and it's FREE, I use that but I'm not sure if it's compatible with Mac.
@Waj, not to get off-topic or anything, how'd you get that Youtube Partner stamp? Kind of curious lol.