So, you make the thread a little deeper and you have like, a ratcheting type deal thread on, then you attach multiple cogs to the ratcheting mechanism. You would need some sort of device to make the chain move from cog to cog, but it would be cool, man! It would be just like a fixed gear, but not! So long as we don't call it a "freewheel" or "coasting" or "gears" or "derailer" no one will think we're losers!

You can give me all of your money now.