Hammarhead Industries of Philly have made out of a carbureted Triumph Scrambler. The engine internals are pretty much untouched, but suspension, carburetion, and exhaust have all been lightened and improved with performance parts.
This is how road bikes were converted for off-road use before specialty enduro and motocross bikes became commonplace. It's cool, but a bit too light and spartan for me, not to mention the cost of those performance upgrades.
Discovered via BikeEXIF