Combining a jet ski with a four-wheeler might sound crazy — in fact, it is a little crazy, but it's also awesome. The Quadski ($TBA) is exactly that: a four wheel amphibious vehicle that tears it up on land and sea, with a top speed of 50 mph on either surface. Granted, we doubt it's as good on land as a regular ATV or on water as a jet ski, but when was the last time you were able to drive your jet ski to the beach? [Thanks, Matthew]