If you have decided that the riding in your area is over, now is the perfect time to do some upgrades. You now should have much more free time on your hands since you are not on the mountain, and customizing your snowmobile is now the perfect project. One of the first upgrade's you should consider is a exhaust canister. They will drop pounds off your sled, increase the power and performance, and make your sled sound better.
I have rode on many different sleds that had different cans on them, and I by far like the Skinz Super Q Silencer that I have on my sled.

This can gave my 09 Polaris 700 RMK unbelievable power and made it sound great. It made my snowmobile drop 15 pounds which is a huge amount of weight. It was also very easy to install and came with a 3 year warranty. If you enjoy racing, mountain riding or ride in lower populated areas, this can would complete your sled.
If you want to hear the difference between this can and a stock Polaris can, go to:
http://www.youtube.com/watch?v=vaQcLy5lEfY