Stealth Slide

Stealth Slide is a power-up used by Sly Cooper to slide at high speeds. It can be purchased from ThiefNet for 650 coins in "The Predator Awakes" of Sly 2: Band of Thieves. It uses a small but steady amount of the Gadget Meter.

Description
Holding the assigned button will create blue spheres underneath Sly's feet that allow him to slide around a level. While it is possible to go up hills with it, it is difficult as gravity will pull you down. Thus, the proper way to use the stealth slide is to activate it while on downward slopes.

Guards will not hear you while using the stealth slide, so in some situations, it is better than sprinting.

Trivia

 * Stealth Slide was replaced with Rocket Boots in Sly 3: Honor Among Thieves. They serve a similar purpose, though rather than sliding, Sly is propelled forward.