3x3 ball maze inspired by http://www.thingiverse.com/thing:1542 Not exactly an intellectual challenge, but an interesting print!

I still find it amazing that it's possible to print these vertical columns.

Print, clean up inside the top (the overhangs are a little too much), play.

Alternatively, print ball in a different colour first using support material, clean it up to make it a perfect ball, then drop it into an empty maze halfway through the print to really confuse people.

Update: I've thickened up the outer columns and the ball was also a little tight, so I reduced its radius by 0.5 mm updated files attached.