D&D 2nd Ed.: Dwarvish Necrobane. Guy had a pair of empowered holy axes that disintegrated reanimated flesh and the burrowing ability. Went to a town with a vampire problem and basically swam through the graveyard during the day and wiped out the lot of 'em. DM might have been giving me a little bit of leniency there for artistic flair, but mostly the dice rolls just REALLY smiled upon me that day.
D&D 3rd Ed.: Probably my absolute favourite character, a Half-Orc Druid with (kid you not on the rolls) Modified Int. of 2 (rolled three ones and a 2), Wisdom of 18, Strength of 20, and fairly average stats everywhere else. Guy was too stupid to learn a language, but was the ipso-defacto troupe leader when in the wilderness. The party bought a special caravan with no windows and lots of shiny objects inside to keep me busy whenever they had to go in town, as civilisation freaked me out WAY too much and I'd wind up going on a rampage if I saw any of it.
V:tM: Never really got into the game much, and this was a character I drew up after my first one got ashed, but I never got to play it because the game got scrubbed the following week, but I made a True Bruja who was Ponce de Leon's first mate. de Leon had actually found the 'fountain of youth' (vampirism), and had shared it with his most trusted adviser (me), but it drove me mad and I wound up diablerising him. Went on a 100 year rampage before I was torpored. When I came to and saw what my wrath had done, became extremely repentant and joined up with that faction that follows Osiris and has to maintain a humanity of 8 or above (can't remember what it was called, again, never really was all that into V:tM)
V:tR: Made a Mekhet that was based on the doctor in that one scene in "Rules of Attraction". He was a surgeon with quite possibly the driest sense of humor ever. REFUSED to stay in Alysium or anyone's lair. Instead, bunked down in a different YMCA every day, preyed on the various athletes who stayed late. Never killed mortals because he obeyed the Hippocratic Oath, but if he encountered an antagonistic vampire, would often say something like "Now then, this isn't right. Young lad, you have no pulse! Clearly you shouldn't be walking around. Well, we'll have to fix that now, won't we? Let's see, where did I put my scalpel? Nurse..."
Call of Cthulhu: Made a guy called Chauncey "Cannonball" Wilson who was one part Teddy Roosevelt, one part Paton, a heaping helping of Archchancellor Mustrum Ridcully, and a helluva lot of 1920's piss and vinegar. Guy was serious old money, owned a personal dirigible piloted by a pygmy named Mandalay, had his own Chinese driver named Hong (we rolled up the guy per the actual rules of character creation. He wound up being the CoC version of Kato from Green Hornet). Had a custom made .30-06 Springfield dubbed "Petunia" that NEVER left his side and was "all the woman I'll ever need". The hilarity was magnified by the fact that I rolled one under the largest possible size and the absolute lowest dexterity. Freakin' ZOMBIES acted before him in initiative order. But the guy didn't need speed. Let's just say he earned his nickname "Cannonball".