Guys,
I use Onetel for my phone calls which saves a bundle compared to BT - especially to overseas. Anyway their ISP connection is 1p a minute anytime of day. No waiting till 1800 with everyone else. Fairly reliable and they have an 0808 access number. This is effectively free to the phone you dial on (ie Heathrow Hilton) and goes onto your home bill at that 1p a minute.
Reliable connections and pretty fast data rate.
Plus very little spam.