HoudahGPS is a freeware front-end to the open source command line tool GPSBabel for Mac OS X.
HoudahGPS 1.0 allows you to transfer track log and waypoint data from your Garmin, Magellan or Wintec GPS devices. It connects via USB to the Garmin and Magellan devices. It interfaces with the Wintec WBT-100, WBT-101 and WBT-201 devices using Bluetooth.
HoudahGPS also allows users to convert between the GPX, NMEA and KML log file formats. The Sony GPS-CS1 track logger uses a special variant of the NMEA format which can also be read.
Possible uses of HoudahGPS include:
• Creation of backup copies of track log files for later use with HoudahGeo
• Conversion of track logs to KML for visualization in Google Earth.
HoudahGPS is a freeware product based upon the open source command line tool GPSBabel.
More info, screenshot, and download link: http://www.houdah.com/houdahGPS