I saw this deal when I was doing some testing on price comparisons. You can buy Buzz! World Quiz for the PSP for only £8.99 from Shopto.net. I think this is a great price, as the next available online price seems to be £12.24 @ CDWow, so it's a few quid cheaper than that.
"The PSP version sees a whole raft of portable Buzz! firsts that makes it an irresistible offer to people who like to take their trivia on the go. As well as the 4,500 questions that you get with the game, Buzz! Quiz World gives you access to the MyBuzz! quiz online portal so you can personalise your quiz with questions that you and other players have written - previously a PS3-only feature - and you'll also be able to download extra quiz packs from PlayStation Store to tailor your game to your favourite topics."