Actually, the formal name of this group is the Yeomen Warders of Her Majesty's Royal Palace and Fortress the Tower of London, not to be confused with the Yeomen of the Guard, a completely separate organization. Confusing those two will mark you as a complete moron. I learned that from Wikipedia. Speaking of which, feel free to turn "What am I, Wikipedia?" into the hot new catch-phrase. Saying that will mark you as a hip, cool follower of Deadpan Inc. to those in the know.
Here's a photo of Moira Cameron, the first female Yeoman of the Guard in their 1,000-year history. Seriously, dudes, couldn't you wait for the second female Beefeater before starting with the dirty talk? Way to sully history, Beefeaters.