Probably your best option is clearwire, it doesn't involve any antennae and you can bring it with you if you decide to move.
It has some advantages-or disadvantages depending on how you look at it- Peer to peer sharing -limewire for example, is banned from their network, so you are ensured that you will get a good connection on an uncongested network, which can make all the difference if you are using voip.
The alternative is Digiweb Metro which is an antenna on your roof and includes a voip package-but check the call rates!
Patrick