I've been using BT's Home 500 ADSL for nearly two years.
Initially it was nearly £40 per month but now only £29.99 per month - and the self install is a no-brainer !
I must say that it's been very good and very reliable - and when I did have a problem ( only just the one, about 18 months ago ) the helpdesk and support couldn't have been better.
Putting it into perspective, my wife and kids use it a lot ( as do I for VPN access into our office ), it's on 24/7, it's fast, it always works, there's no dialing-up ( mostly because of the way that I've configured my router) and all this only 99p per day !
Nb. You can spend a bit more ( as I did ) and install your own Router which will then allow always-on connections, plus alllowing multiple PC's in your house to use the same ADSL connection ( albeit that this is often against the terms in their contract for the service ) and better still if you get a wireless enabled Router and you'll then be able to use your laptop from pretty much anywhere around the house / garden.
Yes, BT's not the cheapest but it DOES work ( at least it has for me )