A couple people were interested, so I thought I would describe the connection between laptop and gps via a homemade cable. A photo of the back of both units is shown below. The Magellan GPS has four copper pads for connection via their expensive cable. The essential connection is between the two pads shown and the illustrated pins on the serial port of the laptop (or any computer). Circled yellow on the right is a 9 pin connector from Radio Shack (2 bucks) which will plug into the serial port. Wire it to make the connections (shown with the colored lines) and the GPS will continuously spit out coordinate data to the computer. Plot programs such a SEACLEAR (freeware from www.sping.com) will look for this data on the serial port and will plot it on a map.