Bobsled

The Bobsled is an item first appering in Sonic Rivals that is used in place of the standered snowboard to quickly travel across snow and ice.

Sonic Rivals
Bobsleds only appeared in Crystal Mountain Zone Act 2 of Sonic Rivals although in this game, the bobsled receives a completely new design and are motor-powered and the player just needs to jump onto the bobsled to start moving, making them somewhat more of a resemblance to motor snow-skis. They transport the player's character throughout one large section of the act fairly quickly.

Sonic Unleashead
The Bobsled shows up once again in Cool Edge during the day.

Mario and Sonic at the Winter Olympic Games
The Bobsled shows up once more in a team based event.