you can set the 770 to maintain connections with the cover on. its somewhere in the configuration app.

you can find some command line lovin in this thread...
http://internettablettalk.com/forums...ead.php?t=9577

as that thread shows, kismet will work with a GPS, if you configure kismet to do so. there is also another package for the 770 that you need for kismet to work with a bluetooth GPS, but the name escapes me.
EDIT - the package you need is gpsd for the 770. the n800 comes with it in the default firmware build. check maemo.org download area for it.

i am not sure what else you would want to do with the GPS without an app such as maemo mapper or kismet, as you would have to decipher the NMEA sentences that it gives.