Oooh, coloring is a good one. Kind of along the same lines (haha, didn't mean to pun there)…. are you familiar with Picasa? You can edit photos in it. Of course there are many other programs too, but that one is good when you want an easy one. They have a bunch of effects you can play with. If you don't like it, all you have to do is click "undo", and it'll undo the step you just did. And then you can try a different effect. You can do a whole series of effects so you can make it into a very different image from what you started with and they can be very abstract and fun.

Also, are you familiar with Electric Sheep? Here's a nice long one:

Full screen it and just watch. You can watch either in a relaxation kind of way, or in a more active way, trying to figure out how the pattern is actually moving. They're mesmerizing. The first time I stumbled into them, I don't even know how many hours I spent watching them(!) I was absolutely enthralled, and found that they totally occupied my mind without stressing me out.

Hope you find these ideas helpful.
And please be down on yourself for using your meds -- that's what they're for after all -- to help you mellow out your symptoms.
Sending lots of positive thoughts your way….