My favorite Star Trek: TOS character, hands down, was Chief Engineer Montgomery Scott.
Alas, James Doohan has passed away today at 85.
[Update:] Whoa! The Free Press had another, more detailed obituary with fascinating details about the man's life:
At 19, James escaped the turmoil at home by joining the Canadian army, becoming a lieutenant in artillery. He was among the Canadian forces that landed on Juno Beach on D-Day. "The sea was rough," he recalled. "We were more afraid of drowning than the Germans."
The Canadians crossed a minefield laid for tanks; the soldiers weren't heavy enough to detonate the bombs. At 11:30 that night, he was machine-gunned, taking six hits: one that took off his middle right finger (he managed to hide the missing finger on screen), four in his leg and one in the chest. Fortunately the chest bullet was stopped by his silver cigarette case.
Then there's the fact he had nine children, the last of whom was born five years ago.