In Photoshop, the pencil brush is exactly what you are looking for. You also have to set your eraser to 'pencil' and check anti-alias off from the other tools (line tool, bucket fill tool) I use Photoshop for most my pixel art. I find the posibility for layers is well worth it. You can also animate your gifs directly in Photoshop.

Most of us can't afford it. :(

Wow. I'd never, ever used the pencil tool. I didn't even know it existed. That's awesome.

Also, Photoshop was extraordinarily cheap for me, as I purchased it through our Uni and thus got crazy-cheap student rates.