Maplin are doing a special on a (non hard disk based or wireless!) [broken link removed] for €67 right now. See what Argos have too. As mentioned above few mini hi-fi systems will approach a good (but more expensive) separates system for sound quality but it's horses for courses.
BroadbandKen - you seem to be more in the market for some sort of PC/wi-fi connected media device rather than the sort of mini hi-fi system that the original poster is looking for.