I'll give a big thumbs up to the Planet-X ones. Got 'em for a fiver during a sale in the summer. Nice and warm, keep your feet dry and reet easy to get in and out of. Look kind of goofy off until you actually put 'em on.
I used to have all kinds of disdain for these kinds of things, but now I'm older I really do appreciate having dry feet on really wet days esp as my cycling shoes are about as water proof as toilet paper.
On-One/Planet-X always have em seperately, or as a bundle like this (with beanie and gloves)
http://www.on-one.co.uk/index.php?mo...ge&PAGE_id=199