As a child I was obsessed with the surname O'Sullivan (from Enid Blyton's O'Sullivan Twins series). Ironically, as an adult I took my DH's surname which is an Irish name starting with an O' and it's a pain in the arse on a regular basis - misspelled on airplane tickets etc...
I quite fancy the surname "Barnard" but that's because I have a strange crush on the actor Aneurin Barnard currently ;)