I think all characters have a facet or two of their creators in them. Not fully the Rper but similarities here and there. Especially when someone is just starting out in the RP world. Think one of the reasons people have a hard time staying true to character concept is because they make them too much like themselves or start shifting from what they wanted the character to be to themselves since over time it is easier to just type your initial gut reaction instead of thinking within a characters own mind. One the flip side having one or two traits in common with your character can make it easier to stay in character for the traits that aren't in line, an anchor point if you will. 

	Now, onto the actual question. Yes, I have one that is me. Fully me. Even named Jenn. Why? A friend of mind hosted an Rp and wanted to do a Self-Insert RP. The group went along. We had to draw up our stats based our actual selves. From intellect, to strength, reflexes, etc. Your character could only have skills you actually possessed. Then we were thrown into an Rp setting and had to face the various scenarios he threw at us. That had to be the most challenging Rp for me to do. You had to look at yourself, really. Not what you wanted to be, or what people told you to be nice. It was a tough introspective. Even tougher to Rp. One might think rping yourself is easy but when you are limited by yourself, by true stats, by not what you want your character to do but by what you would really do it makes you take a hard look at yourself.