Either Amazon or Fishpond, where they would go towards books. I might share the love, but I think I'd probably use most of the gift certificate on material for my thesis (ostensibly to pad out my already-overflowing bookcase too, heh). Despite working for a tertiary bookshop and being able to get books cheaper than I would if I went to the university bookshop on my campus, most books on early Christianity are actually cheaper to buy overseas than they are to order through an Australian distributor (they usually arrive here faster too, particularly if they're coming out of the UK). There's actually a debate going on here at the moment about overseas book imports versus Australian books. I'm kind of torn on it (overseas imports would put a substantial dint in the profits of the bookshop I work for), but personally it is better for my budget to go online and overseas for resources rather than locally.
Watched Law & Order: UK last week. Lord Tony and Fumier from The Scarlet Pimpernel shared a scene, and I sighed wistfully and wondered if Chauvelin would turn up in judge's robes (will anyone get that?).