I recently got a new shiny Garmin Handheld GPS receiver (GPSmap 76C), and I’m really impressed with the mapping. However I’ve been brought up on OS maps and find Grid References easier to use than lat/long, so the National Grid comes naturally, unfortunately such units don’t feature grid-lines. But not any more, download Grid-lines for a Garmin device here. I include plain text files in case others can convert the mp files to something for use on other devices for example!
(could be said to be following in the footsteps of a very similar feature for Google Earth 
, with interest could even create a UTM version – but would be much bigger files due to the greater coverage )
