Too smart for their own good sometimes.
A few weeks ago I came downstairs to find the cork lid off the pasta jar and the jar I keep cat biscuits in, with a few bits of both scattered across the worktop. I thought it odd, but cleared the worktop, threw away the bits and put the lids back on. The jars stayed in the same order on the worktop....the next morning ONLY the cat biscuits were open and there were a couple on the top. A bit of detective work clarified that Darwin had figured out he could hook his claw in a cork lid and open the biscuits.....
The thing is, he had biscuits down - I think he must just like a challenge!