30Gb is pretty low end here (Australia). Eg, here's a price list for Internode: http://www.internode.on.net/residential/broadband/adsl/easy_.... The base plan is 30Gb/month for $40, the high end is 1Tb/month for $130.

iiNet's base plan is 20Gb/month for $30: http://www.iinet.net.au/broadband/plans.html

Telstra has a 2GB/month plan for $10, but that is really just there so they can price gouge people who don't know better: http://go.bigpond.com/broadband/?ref=Net-Head-Int-Plans-Broa...

I don't know what lets T-Mobile sell 3Gb as "unlimted", but they wouldn't be allowed to call it that here.