SSB xceivers cost <$700. Try any marine electronics store. Best choice is a ham xceiver with strap selectable SSB (actually a violation of FCC dictate to enable SSB on a ham rig, but everyone does it anyway). This would cost ~$1500, the Icom 7658 is a good one I know of. Go and get your local equivalent of a VHF license, send in the extension to cover SSB (~$50). Then purchase a 'PacRat' from any ham hangout. I got mine in Redwood City CA, on El Camino real - some years back now though. This is a little box that hooks into the back of the ham/SSB set and into a serial port of your PC. It comes with some basic packet handling software. Last time I looked, PacRats were <$200. Don't expect any great xfr rates however. Noise to signal requires many packet retransmissions as the ionosphere is not a very good mirror. Running TCP/IP over it should be easily doable. Basic use is to dial in the frequency yourself on the SSB (this usually requires an auto-tuner ~$700 AND a manual tuner ~$100, for best results). You need to get the best antenna you can afford. Unfortunately, antennas are frequency range specific, so you'll probably need 3: one for 0-5000 miles, 5000-12000, 12000-?. Its easy to rig the tuner to support 2-3 antennas, switch selectable. You need a Good Earth for anything to happen as expected. By now it should be possible to get some extra SW to drive the freq selection, so you could do spread spectrum. This is not allowed of course, as you are expected to do the call-sign exchange protocol on each freq session. There are freqs that are dedicated to digital (ship-to-shore commercial). You may have to get a commercial license for this though. One nasty thing about radio is that you share the spectrum with others, so collisions tend to make a hash out of reliability. Store and forward at unpopular times such as 3:00 EST, could be a good alternative. The longer distance freqs (>12000), are the most uncluttered, but suffer from the most noise to signal. A bounce across the pacific to the house next door, would be potentially more reliable than a lower freq. Most of the ham sets also support FM, so it would also be possible to piggyback on the ricochet freqs for line of sight use. Or for a real adrenaline rush, piggyback the mil freqs. If you really want to give the hams fits, write a noise to morse engine (or better yet, some captured call signs repeated endlessly) and swamp the channels, where the old popular mechanics guys discuss their antenna envy, at random intervals. 9:00 in the Ozarks is a fine time. Sit back and wait for the black vans to drive up. "Educate, don't Agitate"