Lowrance XOG. the battery only lasts a little over an hour but its portable and ram mount make tons of different holders - boat, atv etc. If you are into fishing you can also buy the navtronics or lakemaster chips that show in anywhere from 1-3 foot breaks. boat launches, bottom structure... We have used them in -20f when we ice fish and the LCD still functions well. It does regular, birds eye, voice navigation and comes with a media player.
http://www.amazon.com/Lowrance-000-0.../dp/B000Y1X4EO