Dear Widget, Spike, Bob and Harry,
There's a trick to opening cabinets wherein you stand on your back paws, put your front paws on the lip of the cabinet door at the top and then walk it slowly backwards until it's completely open. Then you can waltz in and out at your discretion or convince your fellow kitties to climb inside and push the door shut on them.
Bonus: If you lose your grip, the cabinet doors bounce shut with lots of fun "band" sounds, which annoy your human servants to no end. Double bonus if you do it in the middle of the night.
Sincerely,
Prometheus
PS: Tesla says that if you play your cards right in choosing which cabinets to open, you sometimes get rewarded with awesome stuff like plastic bags to play with. And on occasion they have people food in them, which is no bueno for eating but muy bueno for playing with!
PPS: Try not to get caught doing this if you keep waking your humans up with the cabinet-banging. They'll go to the store and buy something for the door that keeps it from opening anymore at kitty paws. But the human servants can still open them. It must be a size thing. Maybe if I put on a few more pounds, I'll be strong enough to open the darned things anyway...