Has it ever been done ?
Whats a rolla bolla?
Im sure someone has done it 
I know that Steve-O has done it on a skateboard. A uni would be tough
Yes it has. I’m pretty sure I’ve seen a video of it either on youtube or at my school’s library. It would be almost impossible that no one has ever tried it though.
thats awesome cause i wanna learn it, i think it would be a good thing to do in busking. It’s on the spot, incredibly difficult and the crowd will drop jaws all over the ground lol
And put the rolla bolla on top of a table or something like that.