get an iphone and download the "motionx-gps" app. Only £1.79 (or something like that?) and it's very good vfm! Measures top, current and average speed, distance travelled and it highlights your trails using satellite images.
Can stop to take a photo and save it to your trail and u can also listen to the songs on your iphone while using the app. More over, you can send your trails to your friends so they can follow / find your current position and if you go off the rails it has a compass (if you have a map) and locates your coordinates should you need to get in touch with mountain rescue, plus ..... it's still a phone!! Not tried it on the slopes yet but it's an excellent jogging toy. Will be putting it to use in
Les Deux Alpes in March though!! I imagine if you used it all day you'd be talking to a dead phone? Battery life on iphone is poor at the best of times.
Mammut Safety Inclinometer might also prove to be a useful app? Has avalanche warnings, weather forecasts etc etc... This is a free app too.