I've used and had good success with DriveImage XML, which can "hot clone" your drive while you're using it for other things, so no rebooting and waiting required. The fact that it's free for private use is an added bonus. The UI is slightly clunky, but tolerable considering the price (or lack thereof).

For the Mac crowd, I've used Carbon Copy Cloner several times with good results. Many other options fail to clone the recovery partition, and the new disk works perfectly fine until there's a problem and you can't recover. Well worth the $40 bucks I paid for it, since I've gotten several uses out of it for family and friends as well. They also offer discounted upgrades when the newer versions are released so I go ahead and keep current so I have it when I need it. You'll have to use something else to clone the non-mac partitions if you're a dual or triple booter.