Currently, I'm getting wireless internet exactly the way you envision it. It can work. You pretty much just need the antenna and a router.

What I've got is basically a little wireframe antenna, on a pole on the roof, connected to a special piece of super-thick low-loss antenna cable, that connects to a homebrew wireless router. The homebrew wireless router is actually an Orinoco PCMCIA card with an external antenna jack, pigtailed to the thick antenna cable. That card is plugged into a little single-board 386 computer running a customized Debian that boots off of a flash card. That board-computer is the router. It was all designed, built, and programmed by my ISP.

You could probably accomplish exactly the same thing with an off-the-shelf wireless router and an external antenna.

BUT... Before you do it... Consider these points:

1. Reselling his bandwidth to downstream customers, your neighbor is probably breaking his contractual agreement with the service provider. So you could both get in trouble for doing it if you get caught.

2. I'm getting my service for less than half the price your neighbor is paying, and I'm doing it legally. I think he's being robbed, and you guys should confront the ISP about it.

3. Your neighbor might not be getting the full 11-megabit bandwidth. He might be getting a subset of that bandwidth. In which case, you guys will be fighting over the available space any time you're on the line together. This might not be a big deal for you guys, but you should check into exactly how much bandwidth that $99.00 is getting him.

4. Your in-home wireless network will interfere with the uplink to his wireless network, unless you're careful about configuring the routers.

5. Your directional antenna, at your end only, might be enough. But if it's not, then he'll have to set up a similar antenna at his end. This gets tricky.