Little did I know that my Garmin (Vista HCx) can save GPS tracks with the timestamp intact! This is great for geotagging photos, loading timed tracks into Google Earth, etc.. Up until now the only way I knew to do this was to not save my tracks on the GPS and get the 'active log' from the GPS. A clumsy process. Here's a better way:

As far as I can tell this only works for Garmin models with an expansion card (MicroSD)

On your Garmin GPS: Go to the Main Menu -> Tracks -> Setup -> Data Card Setup.

The 'Log track to data card' should be checked. It then will save your track files to .gpx files on the MicroSD card. If you don't have one you should! They are very cheap and well worth it! It is important to note that the tracks don't show up on your saved tracks page. They are just stored on the card.

To get them turn your GPS in a USB mass storage device by going to Main Menu -> Setup -> Interface ->USB Mass storage

Then just plug your GPS and open it like a drive. You'll see a lot of GPX files sitting there waiting for you!

All of the tracks will be in a GPX format which look like this:

<trk>
<name>ACTIVE LOG070216</name>
<trkseg>
<trkpt lat="46.260431" lon="-63.131050">
<ele>31.502</ele>
<time>2007-10-30T10:02:16Z</time>
</trkpt>
</trkseg>
</trk>

The GPX files can then be easily converted to .kmz or .kml files for viewing in Google Earth/Maps.

Enjoy!