Aha!

I found out why Felicia Day from 'The Guild' looks so familiar. She was one of the potential Slayers (Vi) in the last season of 'Buffy: the Vampire Slayer'.

What Wikipedia has on Vi:

Vi
Vi is a Potential Slayer who arrives in Sunnydale in the seventh season, and is played by Felicia Day. Vi was trained by her Watcher prior to her arrival in Sunnydale, but her experience with the supernatural amounts to seeing a blurry photograph of a vampire. Introduced in the episode, "Showtime", the timid Vi initially seems unfit for her calling. However, she proves to be a courageous fighter during several battles, including the final battle in the Hellmouth. She survives it and, though having been wounded herself, helps treat other wounded such as Rona and Robin Wood in the aftermath. She appears in the comic story "The Chain", starring alongside Andrew Wells in a television commercial informing recently activated Slayers about the Watchers' Council.

If you haven't seen 'The Guild', you really should, especially if you have any interest in gaming online or off, because you'll be more likely to get the jokes. It's up to episode 7 and they just keep getting better and better.