I haven't tried it yet, but I'm going to. Granted, they don't handle water well, but even in a small boat, surely there's a place to keep them dry. Buy a used laptop, if you don't want to risk your good one. You should be able to pick one up, that will do, for $150. Hardwire that puppy to your battery, carry a garbage bag to through over it in big seas....and you have a big screen GPS with a keypad! Oh ya, you need software and a GPS interface.....try Fugawi (www.fugawi.com), not really cheap, but good, I've heard.