I had a cat who would play piano with me. She'd pick two keys and rock back and forth on them while I practiced.
When I had a regular, corded phone, my cat Will would knock the receiver off the base (right by my head) to wake me up. Usually at about 5:00AM, when he thought I should get up and feed him. Will also knows how to turn my stereo up. He gets into the (open) closet where I keep my equipment, stands in the space in the rack between my computer stuff and my AV stuff, and butts his nose against the volume knob (Will has a thing about itching his nose). If I don't keep the door to the half-bathroom shut, I wake up in the morning to the steady hum of a completely cranked receiver. Even worse, sometimes I leave an audio source on, and then I awaken to the sound of whatever I was listening to (this is especially funny when combined with Gracie's habit of sitting on keyboards. I've been awakened to DING DING DING DING DING as my game PC protests whatever weird combination of keys she's keeping held down).
One of Amy's cats liked to play with her cordless phone, which got *ME* in a lot of trouble when the cat kept hitting the "redial" button while she wasn't home (kept calling her girlfriend... and I was the only person with keys to Amy's apartment). I only recently got an apology for that - she finally saw her cat actually do it. Amy also trained her catrs to use an actual toilet, rather than a litter box. That's pretty amazing.
Gracie likes to get between me and books. In fact, she'll chew on books, if I leave them out. She's shredded paperbacks. She hates books. And computer monitors. And keyboards are good things to lay on. I think she likes attention.
All three of my cats tell me when bedtime is. Bedtime is basically midnight, plus or minus ten minutes. I don't know how they tell, but they do. Foster stands at the top of the stairs and whines. Will comes and walks between my legs and swats my feet. I think he's trying to kill me. Gracie walks back and forth between my bedroom and whereever I am. When I get to my bedroom the two boy cats run off to play-fight. They aren't allowed in the bedroom. Gracie says so.
I've seen both Will and Foster turn power strips and surge protectors off and back on. I ended up taping a little hard plastic cover over the couple of switches they'd hit most often.