There are a few major free pain programs out there for Mad - Paintbrush and HeliosPaint are two of the most notable.
HeliosPaint is a cross platform option because it is written in Sun Microsystem's Java programming language. This makes it ideal for those that are constantly switching between Mac and Windows but it does have the drawback of Java that means HeliosPaint works rather sluggishly. Sometimes, it seems the program is flickering in and out and changing skins for example, takes a few seconds to take effect as the Java engine updates itself.
On the plus side, it's free to use and offers more options that you'll find in Paintbrush. HeliosPaint is clearly a more complex package although this leaves it in something of a no-mans land. It doesn't offer the cheap and cheerful appeal of Paintbrush but it's nowhere near being an advanced as something as Photoshop. The result is that it's not quite as easy to just pick up a brush and start doodling away. It takes more time to work out the various functions and some can prove simply illusive. For example, working out how to simply delete a paint job is not as easy as picking up the eraser in Paintbrush.
If Paintbrush doesn't quite offer enough for you, and you don't mind working on a Java app, HeliosPaint might be for you but doodlers may be better off sticking with something simpler.
