Amen to Tropical Iceland, definitely a catchy song.
I think most of Wild like Children by Tilly and the Wall is fairly catchy, and
Travis is also catchy, 13 Memories in particular.
Global Eyes by The The, which is catchy in a pretty sinister way.
Even Tom Waits has been know to be catchy, in his own way, on Real Gone, fx. Trampled Rose and Hoist that Rag...