I've considered getting broadband without a phone line before and also not getting the TV channels, but to be honest, I've found the bundles/collections with TV, phone and broadband to be the best value... and much cheaper than in the US.
Just going with Virgin's most basic package of landline, weekend call package, cable TV and 30MB broadband, it's on offer for £25.99 per month for 6 months, then £35.99 after that.
If I just got the cheapest broadband with a phone line but no TV, it would be £23.49 for the first 6 months, then £31.49 after that. So for only a couple of pounds more per month, I could get over 60 TV channels, 10 HD channels, a 500GB TIVO box and free Netflix for 6 months.
If I just got the cheapest broadband with no phone line, it would be £20 a month for the first 3 months, then £25 a month after that. So, for an extra £5-10 a month, I could get the phone line, free weekend calls, digital TV, TIVO, HD channels, Netflix, as well as the broadband.
So, personally, I'd rather pay the £25.99/£35.99 per month and get it all, rather than just pay £20/£25 for only broadband (even if I barely use the phone line
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).