Link: www.maclife.com.
Apple makes it easy to resell your Macs if you purchased an AppleCare Protection Plan. These protection plans are fully transferable to the person buying your used equipment.
Which doesn't mean one shouldn't give it away, just make sure the AppleCare information goes with it so the recipient can truly enjoy his or her "new" Mac [also true of iPods, iPhones, etc., I suppose]
