Got a really good deal on an Xmotos 150cc rolling frame through ebay ($130 shipped!!).
Looks like this but in silver/red, sans ICE, and sans body panels.
Unlike the previous frame I was looking at this one includes hydraulic disc brakes on both wheels, and is compatible with a very wide range of wheel sizes (14" to 21").
Saved me so much money I don't have to worry about cutting/welding where needed. I can then get it powder-coated to my color of choice to protect it from rust.