Just saw the thread...
I've been using this toilet of mine own design and invention for about three years (off and on.) Using it now. Very little smell outside, and none inside. One has to maintain it, but it's not the worst chore in the world.
If I had it to do over again, I'd build more space efficient cube-ish fiberglass tubs to replace the 5 gallon buckets. However, 5 gallon buckets are cheap and easy to come by, especially when one is building in a hurry. More storage volume would be good if more than one person is using it regularly. Going to square tubs would increase the container volume 25%
This company has some buckets that might work.... http://www.usplastic.com/