We use Port Networks' system. http://shopping.netsuite.com/s.nl/c.ACCT117420/sc.7/category.924/.f

We have the predecessor to the MWB 200. Ours box and antenna is in the seahood instrument "box" under the front edge of our dodger. Then we connect with a simple ethernet cable to a router. From there we can connect into the PC and use some other recepticles in the boat.

If you're going to be mounting something on a spreader, then connecting to a bridge at the base of the mast (inside the boat), you can connect with the a ethernet cable to your PC. Getting the antenna up in the air would increase the distance you'd have a shot at a wireless network a bunch -- but....

I think that if you're going to make yourself more "hooked-up", I'd look at the newer Blackberry or iPhones that actually work as a wireless hub. We have MiFi2200 Verizon unit. It functioned at high speeds from Most parts of Penobscot Bay to the Chesapeake. (We were over twenty-five miles offshore of Nantucket and connected in one dark and stormy night while connected into the Internet by Verizon. The little MiFi unit creates its own little local WiFi within a 20-25' radius.)