Mmm, accents are lovely. Being in Scotland, of course I am partial to the Scottish accent - and I prefer the Highland accent (especially from near Inverness) to a more common Dundee one, which can get a bit grating whilst on the train to Edinburgh.
English accents are usually nice as well, I quite like the greater-London area accent, Midlands, and the posh accent that knows no geography.
I'm not really fond of the Geordie accent though from the north - I'm not sure what it is about it though.
Northern Irish and Republic of Ireland accents are lovely in any form.
Hmm, as far as other accents, I do like French (and Quebequois), and New Zealand, though it depends on the person and their intonation.