Though it is not included in a default Hardy install, GNOME 2.22 has a new program called Cheese, similar to Apple's Photo Booth. It has a range of effects available including "Hulk" (turns your skin green), mauve, noir/blanc (black & white), saturation, some crazy psychadelic one, and warp.
Here's Cheese in action (using the "warp" effect):
And here's a pic taken using the "dice" effect:
Photos are stored in ~/.gnome2/cheese/media/ but you can right-click on the images at the bottom of Cheese and "Save As" to save them somewhere else.
My webcam is a Creative PD1030 and worked out of the box, though I wouldn't necessarily recommend it since it's pretty blurry. It could also just have something to do with being second-hand and a dirty lens though.