If you enable Track Logs, you will find that they are stored at \My Flash Disk\MioMap\MioMap2\iGo.db and there are programs to convert this data. You can also export the track log into a gpx file directly with the enhanced skins available starting with Version 3.4.
[UPDATED 2/12/2008 as this portion only applies to pre-Version 3.4 users] …however on the Mio C230, the export button along the bottom of the Track Information screen is hidden, but can be restored by removing the word “hide” from \My Flash Disk\MioMap\MioMap2\data.zip\mio\320_240\ui\tracking_320_240.ui and zipping the file back up. When it comes to zipping the file back up, it has been learned that WinZip version 11 (10 is OK though) is not compatible with MioMap. I use WinRAR and I choose “best” compression but I’m not sure if that really matters.
The exported track logs are stored in \Storage Card\tracks. You will find more here.
GPS Visualizer: Do-It-Yourself Mapping
GPS Visualizer is a free, easy-to-use online utility that creates maps and profiles from GPS data (tracks and waypoints), street addresses, or simple coordinates. Use it to see where you’ve been, plan where you’re going, or visualize geographic data (business locations, scientific observations, events, customers, real estate, geotagged photos, etc.).