A basic 20 Mbit connection goes for about $75 in Europe, that's 1.1 ct / Gigabyte (if my back-of-the-envelope math is correct). 40 Mbit goes for about $100 / month.
Metered is out, flat-rate is the future. The only hold-outs will be the mobile carriers and even there I already see flat-rate offerings.
$5 or $10 / month would not work due to fixed costs and write-off on equipment higher than that. But once the equipment is paid for you might as well use it to its full ability without being penalized further.
I have 110/10M (cable-tv network) in Finland for $53.
More widely available 24/1M DSL goes for $46. Usage caps are unheard of in cabled internet.
Cheap, non-capped mobile internet has recently exploded - caps will be introduced. Our biggest telco TeliaSonera has only capped versions since the launch of iPhone (they were were forced and willing to pay extra).
Other companies haven't introduced restrictions, but since Android-based smartphones became popular in 2010 and currently log the most data usage per unit, this will soon change.
Mobile internet is also very popular with plain computers by using 3G usb-dongles, which telcos give free of charge when you sign up for 12/24 months. Typical offer is uncapped 384k for $6.7 or 1M for $12 (actual rates vary often due to congestion - p2p users are a major pain in the butt with 3G networks). These are available nationwide with no geological price differentiation.
In Sweden broadband is quite much cheaper. The government has been heavily involved in building fiber with subsidies, tax breaks and legal requirements to municipal providers. (IT Bill 2000) http://www.broad-band.gr/content/events/docs/Swedish_broadba...
But it's a good way of solving some of the challenges. But more and more people will start hitting that throttling soon, as people start using LoveFilm streaming, etc.
Metered is out, flat-rate is the future. The only hold-outs will be the mobile carriers and even there I already see flat-rate offerings.
$5 or $10 / month would not work due to fixed costs and write-off on equipment higher than that. But once the equipment is paid for you might as well use it to its full ability without being penalized further.