Latin spells: Tabula Rasa is Latin for blank slate.
Soulful vampires: Randy comes to the conclusion that he's a noble vampire with a soul because he doesn't feel the need to bite Buffy and he helps her to attack the other vampires. Buffy says 'A vampire with a soul? How lame is that?' - which is pretty offensive to both Angel and Spike, really.
Not more rabbits!: Once again we're reminded that Anya is terrified of 'bunnies'. We first heard about her phobia in Fear, Itself.
Suit you, sir: The suit Spike wears for most of the episode is similar to the one he wore in Xander's dream in Restless. It was in this dream that Giles said he looked upon Spike as a son, so it seems only natural that Spike assumes that Giles is his father when he loses his memory.
Branching out in the pop world: Michelle Branch sings her hit record Goodbye to You in the Bronze at the end of the episode. The song is taken from her platinum selling album The Spirit Room, and it's really rather good.
Gaydar: Willow tells Dawn 'I think I'm kinda gay' - she said the same thing about Vampire Willow in Doppelgängland.
Mid-life crisis: Giles does indeed have a red and shiny car - not so much shaped like a penis though. We first saw it in Real Me.
Scottish superstition: Buffy quotes Macbeth when she says 'What we did is done'. Macbeth was written by William Shakespeare and is known as The Scottish Play by superstitious theatre types.
A new monarchy: Xander laughs when he remembers King Ralph, a movie made in 1991. Starring John Goodman, it was about the obliteration of the Royal Family and the search for the next King. Reviews suggest that, unsurprisingly, it wasn't very good.
Pun of the week: Did you get that the aquatically styled, kitten demanding demon was, in fact, a loan shark?
Blessed be: Religion crops up a couple of times. Xander, unsure of his faith, recites the Christian prayer Now I Lay Me Down to Sleep, then the Jewish Shema Yisrael, then the Buddhist meditation chant Om. Also Spike quotes The Book of Common Prayer when he says 'dust to dust'.