Ice momentum is a movement technique that utilizes the ice physics in the level Snowy Mountain and can only be performed in Jak and Daxter: The Precursor Legacy. Ice surfaces are programmed to act like real world ice, converting Jak's momentum into a slide effect that slowly deteriorates in speed over time. However, if Jak lands on an ice surface with built up momentum and immediately jumps, the momentum from the ice slide will transfer into the jump minus the speed deterioration. This allows Jak to cover much more horizontal distance with conventional jumping techniques than intended. Once Jak has initiated the jump off of an ice surface, the momentum can not be redirected, but it can be cancelled with a quick ground pound. The full potential of ice momentum is achieved by diving onto an ice surface with Flut Flut and immediately jumping to transfer the diving momentum into the jump.
Ice momentum is the biggest cause of accidental deaths in Snowy Mountain for new speedrunners due to it being a commonly overlooked technique. It only occurs in one level so it is not prioritized by runners. New speedrunners eventually learn the benefits of ice momentum, usually on their own, and become more familiar with how the movement works. This leads to less accidental deaths and better split times in Snowy Mountain.