BlueGPS is a simple command line tool to download datalogs from the Royaltek RBT-3000 bluetooth GPS receiver under Linux. It was initially developed by Til Harbaum and was improved by Simon Budig. See BlueGPS homepage for more details. I modified the sources a little bit to make it work under 64-bit Linux.
If you're using (and loving) Gentoo Linux, you might want to visit my Gentoo page where you can find an Ebuild for BlueGPS, instead of manually downloading and compiling the sources.
On Debian based systems you need libbluetooth-dev for compiling. Installation is done like this:
# apt-get install libbluetooth-dev