I stole the basic idea from a fella on another board, modified it a bit, and shes working great. Cost 40 dollars total.
It does warp a bit at the door. And the other gent who orginally made this says the wheels will start "grooving" the plastic after a bit. My solution to this is to allow a bit of walking when you turn it. Keep the weight moving side to side just a bit and I have yet to have issue.
You could use a steel drum as well. All in what you can work. no matter what it will be cheaper than the store bought ones.
This not only give you fresh free compost but also enables compost tea...the most under rated amendment/additive out there.
Cheers!
Ross