Player A stands on the head of Player B, their movement may be impaired depending on where A is standing. If A is directly centered, things are fine. If A is backwards it changes their forward momentum. Same for if A is off center, it will push B the left or the right. If A moves their mouse to change their direction during movement, this changes how B is able to move as well.
Using this method, along with the known Jetpack Bug, player B uses Jetpack bug while A stands still on top of them, instead of going directly up as one expects with the bug, A now causes B to have forward momentum which seems to only increase, we deemed it as "infinite" acceleration/speed, as the only thing that would be a detriment to gaining speed would be A hitting the skybox.
With proper timing B is able to deploy a parachute and use as intended to zip around the map and take in the scenery. A can disrupt their flight path/trajectory by using their mouse to turn around to look at various things themselves.
Recreation:
1) Player A stands on the head of Player B
2) Player B (with jetpacket equipped) jumps and starts to fly upwards with jetpack
3) Player B removes jetpack from inventory with spacebar held down, triggering infinite jetpack bug
4) Player A's collision with Player B forces Player A into infinite acceleration (see placement of players description for influencing direction of collision impulse)
Results:
Both players are catapulted at infinitely increasing velocity forwards and upwards