I thought this was interesting. Saw it on CraigsList here in the Austin area.
http://austin.craigslist.org/zip/5522816805.html
In case it gets scooped up & deleted, here's the whole text in the ad. It's not mine, nor do I know the person who did it. I'm pretty sure this has my cement mixer beat in terms of capacity.
Almost a vibratory parts tumbler! This is an almost finished project but I don't have time to mess with it. It started as a washing machine and has been stripped down to basically the drum with central cone and holes caulked up, and the motor rewired to run only on/off and mounted to the original bracket on the bottom. It only needs to have a counterbalance/weight added to the motor so it vibrates more. It currently has only a slight vibration.