Amod AGL3080 GPS Data Logger (SiRF III, Driverless, 128MB, Push to Log)
$69.99 sold by Semsons & Co through Amazon in June 2008
Uses 3 AAA batteries (?)
There are two buttons, one is the power button, don't know what the other button does! The power button turns on a green symbol, when the symbol is blinking, the device has locked onto a GPS signal and takes data every 10 sec or so.

There is a USB cable, and when you connect it to a computer, it appears on the desktop like a usb key drive. To transfer the data, copy the log file to the computer.
To use in Google earth, the .log file must be converted to .kml. I use the macintosh freeware HoudahGPS
Google Earth - Open your .kml file in the program and the path will get plotted and you can play it as a movie within the program. You could save the path to "My Places", but I think the easiest is to keep the original .kml file in a folder on your computer and open it each time you want to see it.
How to change the movie icon - control click (or right click in windows), choose "get info", choose "style, color", then click on "share style", and then click on the icon symbol up at the top right next to "name" and choose an icon; I usually change the size as well.

To make a movie for a web page: capture the movie as it plays in google earth.
I use iShowU (shareware, ~$30) to make a quick time movie: 24 fps, H264 compression
Crop in quicktime Pro.