Painter is known as a natural media tool (which it is). But it also has other pretty nice features in it. Here are two I've discovered so far.
1. Seamless tiles
Making tiles with Painter is fun because you can see what's happening as you stroke. For example, as you make your stroke, just let your brush go off the canvas. As soon as it goes off, the stroke begins on the opposite side of the canvas in the right spot. Once you have some strokes down, you can hold down shift-spacebar and move to any place in the continuous pattern. Odd thing though, some brushes don't work right. They just fall off the edge and don't reappear.
I guess the easiest way is to make a small canvas the size of your tile. Click the triangle on the top of the Pattern Palette, click Define Pattern, start painting. After you are done, you pick Capture Pattern. Then you use it any time you want to fill a new canvas.
2. Color Shifting
Painter has feature similar to Color Mechanic called Adjust Selected Colors. And while Color Mechanic is excellent in zeroing in and shifting a color, Painter's Adjust Selected Colors is better and picking a fuller range of a hue. Also, easier than Photoshop's Select Color Range or hue sliders in some situations.
I would not use this for photo correction, though. But I would use if for photo art. If you want to give it a try, download the snowy_egret.jpg from the photo art forum. Open the Adjust Selected Colors feature, click the background of the picture and slide the hue slider. This gives you an idea. Then check out the other controls.
BTW, during this test some of the color on the egret will shift. But this is easy enough to prevent or restore later.