I wasn't willing to put a sump on my tank without it being drilled either. So I flirted with building my own canister filter. I had a hard time finding a container that I could trust so I decided to build a closed loop system instead. Here's the thread:
http://www.monsterfishkeepers.com/forums/showthread.php?t=185984
http://www.monsterfishkeepers.com/forums/showthread.php?t=185984