You guys are a great help! Thanks for all of the advice!

If I wanted a bike that I could shift on the go then I would put deraileurs back on this bike. However, I want a fixed/singlespeed bicycle that I can manually change the gears for different riding conditions. Sorry, I'm not a purist or a hipster but I do want to try something a little different with this bike.

I guess basically the answer I'm getting is to put a two or three speed freewheel on one side and a surly dingle on the other if I can get the right gearing to match my chainring.