Jen,
 
The best cabinet proofing idea we've ever tried was to buy some drawer pulls
that coordinated with the cabinets and install them in the upper corners of
the cabinet doors, where it looks like handles on the cabinet.  Then get
some heavy duty rubber bands or mini-bungees and band the knobs together.
 
It stopped even our most determined cabinet explorer!  We found some drawer
pulls that matched well enough that our landlord didn't even notice them
when we moved out: they just looked like they'd always been on the cabinet.
It's a cheap project too- all you need is a few bucks worth of drawer pulls,
a ruler to mark the placement, and a drill.
 
Janna and Aron
Einstein, Daisy, and Bandit
[Posted in FML issue 2308]