These are two Cheap UK VPS provider i have found till far: http://www.cheapvps.co.uk (Running for over 1 year now, though network stability is a bit low) http://www.tagbridge.net (Newly born, though, doing good till far) But if you are looking for Best quality UK VPS then you should try one of these: http://www.eukhost.com http://www.webhosting.uk.com I have used all of them, and using WUK currently for one of my VPN node
Are you looking for Linux or Windows VPS? I would suggest you to post your requirements in detail to get suitable offers.