Currently pondering started by Kit on DWAITAS: Major Gadgets that would suit a Time Lord PC and aren't Sonic.
The Seventh Doctor's pocket watch with digital insides is of course only one of several pocket watches to get screen time in the hands of various Doctors - it's a perfect "I'm connected to time, in an old-fashioned elegant steampunky kind of way" prop. The Eighth Doctor posed with one in his main set of publicity pics, and following the not-really-my-style Ninth Doctor, the Tenth Doctor spent two weeks with his essence hidden in one.
But anyway. New ideas too. I could see the portable Time Lock and the X-Ray Specs coming in handy quite often. Uses for teleportation and perfect mimicry should be fairly obvious.
I borrowed the pocket translator, not from Star Trek or indeed from the Tritovores, but from ROM: Spaceknight, since it was the third of three gadgets he came with and the other two were an "energy analyser" and his big gun. (Which I suppose is straight out of Star Trek now I think about it - communicator, tricorder, phaser.) To underscore my point about it maybe being a Minor Gadget, I think he only used it once.