We have a Panasonic tuff book CF27 with 64mb of ram.Its a good laptop but its only got a Pentium 2 processor,
It will run some plotter software but not the latest 3d stuff.
It come with a touch screen and is ideal for us,we are running a dedicated gps ariel, with plotter software and Tide software and its also works with autoroute when not on the boat.
I decided to have it as a backup nav tool and run it through a ssb for weather fax when we need it.
With a Card reader you can use C Map Charts from your main navigator.
We bought it on ebay for £600.00 with a 3yr warrantie.