I tend not to; if I can see the seams, so to speak, it tends to take me out of the story.

That said, in games I've run and played in, one player had Dawn's directly inspired by Saitama and Jet Li's character from Unleashed.

On the other hand, there was a player who couldn't come up with an original name to save her life, and this she gave us Dr. Buffy Summers, Dr. Hermione Granger, and Bilba Bagginzoid the boggan.