I've been using TalkTalk's Talk3 International for 14 months and, at £20.99 a month, it's quite remarkable value for money.
I get free AnyTime UK calls to all local, 01 and 02 phone numbers; free AnyTime calls to 30 different international countries and the price also includes my monthly BT line rental of £11.
On top of that the 2MB broadband service was switched to the "up to 8MB" service in March, when my local exchange's TT LLU equipment came onstream and I get speeds of 6MB to 6.6MB.
My best mate got BB at home for the first time last month with the same package and was fully connected within a fortnight.
If you want free international phone calls as well as UK, you have to pay the extra pound a month (unless you are discussing the three month trial period). At 25p extra a week it's well worth it.