To tag on to @saosmash 's mention of our brief foray into F&L and the amazing character relationships there, I deeply enjoyed playing my first nations Nevada ghoul. Wendigo renamed herself into the creature she thought that @Caryatid 's lovely vampire created and slowly cast aside the difficulties of her mortal life for the more insidious dangers of the masquerade. Far older than some of the vampires her humanity lingered only by a thread and the stories she grew up on. It was incredibly interesting to explore her and delve into the history of the area. Also to be a semi-babysitter to neonate babes. Unflappable ghoul.
Vega at X-Factor has also been one of my recent favorites. A mutant hiding her mutation, working as a cop to try to usher change in from the inside. With bubblegum pink hair. She was a dry sense of humor with a mutation that leaned towards practical mechanics in an increasingly cybernetic world and hostile world. She also had a pair of rocket legs. Which was beyond fun.
Oldie but a goodie: Ian at BSG Ouroborous. My Hyperion, surfer nurse who found himself caught in the first war. Most notably had a book thrown at him and carried an ear around for an entire scene because the monkey gave it to him.