The phone company Hutchison Telecommunications Australia, which is partly owned by Hutchison Whampoa of Hong Kong and owns rights to the Orange name in Oz has been offering this in a similar manner now for almost 5 years.

You pick a “local zone” when you buy the phone and can change it from month to month. Calls made within that local zone are charged as landline calls.

Calls made outside the local zone are charged as mobile calls based on whatever plan you are on. I believe it’s an option on their new 3g network as well, tho don’t quote me on that.