I'm shocked. We are with BT and have been paying £37 a month for the top package with unlimited usage (plus line rental). If you ring your provider they tell you what your actual usage is. Ours is actually less than 2gb a month (= fair bit of MNing and internet shopping/browsing then emails no freqent downloading of movies or music) Ours means that BT will reduce the price down to £7.95 (for which they'll give us 10gb five times what we are using, so plenty )or if we switched to Sky it would be completely free!
I'm shocked that I've been paying so much money for nothing!