I was browsing Tumblr and I came across a new piece a software for the artists on this site. It's called FireAlpaca. From what people tell me (and from the look of the site), it's like a combination of some elements from both Photoshop and PaintTool SAI. But it's free, it's compatible with both Windows and Mac OS X, and it's most likely going to be updated regularly (unlike Sai, which hasn't been updated since 2008).
I'm no artist, but I still highly recommend giving this a try. Thanks for reading and happy arting! :3
