This goes about as you'd expect it to.
Ken Block and Jay Leno are two of automotive YouTube's biggest stars. The two recently got together for an episode of "Jay Leno's Garage," albeit the television version, not the Internet series. Anyway, this teaser clip shows Leno and Block attempting to revolutionize the United States Postal Service. Their solution is the 845-horsepower Mustang Hoonicorn. This thing is seriously insane and as you might expect it's not very good at delivering the mail. It does perfectly fine when it comes to drifting around mailboxes, though!
Check out the clip to see Leno, Block and a very unimpressed member of the USPS.