Crazy Dirt Sledding Pulled by MX Bike [Video]
We took things even further than these (equally awesome dudes, anyway), as we sled on rocky countryside roads, which made the adventure even more stupid and dangerous.
However, if you want to get a douse in a sea of pure fear and adrenaline, find a deserted road with no traffic, get your sled, strap on your helmet really well, maybe add some more protective gear, tie a strong line to the bike ridden by your demented buddy and instruct him to ride in a straight line.
This is going to be an exhilarating (though very silly and dangerous) experience you'll never forget, even if you don't break a limb, which is very advisable to try and avoid. And you don't even have to be a bit tipsy as we were: things are insanely mid-blowing as they are.
Oh, and ask him to pay attention to your screams: he can ride for miles, but several thousand feet will be more than enough for you, trust me!