This appears to be a usb broadcaster:

http://www.actisense.com/HTML/Produc...%202/index.php

This is a usb to nmea 0183 converter (both in and out).

http://www.actisense.com/HTML/Produc...eway/index.php

Just take one of these to yur usb keypad or whatever run that to to input of the 1 to 6 (4?) buffer ... take the 6 (4?) buffer outputs to 6 more of the gateways and plug into yur computers usb ports!

I havn't looked up the prices but I dont think it will be cheap (7 converters and 1 or 2 buffers).

Its a 1 to 6 for sure but there are only 5 screwin things - obviously you can put 2 or 3 wires in each screwin thing ...