GPS Ski Resort Maps
Our friends over at Snow Skills have written about a product that allows you to download ski resort trail maps to many Garmin GPS receivers. (Link at end of post.) The maps are only available at certain resorts, mostly in the Western US. Once the maps are downloaded you can view yourself on the ski resort map from your Garmin GPS receiver.
You can also upload your GPS tracklogs to the website and view your movements on the ski resort maps as well as look at elevation profiles and statistics about your day of skiing. The maps cost about $5 each to download but uploading your tracklogs for viewing on their website is free. Mac users are out of luck.