I almost always play female characters given the chance in video games, while maybe 40% of my tabletop RPG characters are female. In the tabletop games they are almost always direct imports from one of the many story ideas I have floating around my head (which I really need to get around to actually writing down one of these days...).
In video games, I usually default to playing Minima Maximus, an obsessive hoarder who never uses any consumable items unless necessary to obtain maximum permanent stats, tries to help as many people she can (taking all of their worldly belongings as payment, whether they agree to it or not), and is generally full of herself in dialogue. These traits mainly came about due to my desire to make the game harder via self-imposed challenges, obsession with 100% completion, and general difficulty with playing evil characters.
Speaking of which, I have the opposite tendency regarding evil characters as some other people in this thread have mentioned. I find it far easier to play an evil character if they are male. Probably because I tend to be rather more protective of my female characters (ie, "No, they aren't really a bad person!")