Indeed, not bad.
I don't see why it would be that ghetto to just get what ever kind of non-slip matting and glue it on the bottom. Use some strong glue, it'l be hidden by the unit, right?
Or, it could also just be a temporary fix until you find some feet, if you just sit it on top of a circle of nonslip. No glue necessary, just figured if you wanted to make it permanent.
How about one of those rubber grips for opening jars? That would work perfect I bet, they're about the same size as a volcano bottom maybe. They're like two bucks at the supermarket. Again, just as a temporary fix so it doesn't slide off the table and break while you're looking for feet...