mogwa - Yep - 2 of ours do that sometimes - or if theres neatly organised piles of paper of the floor being sorted- diving into them, sliding around like a rally car then legging it. 

Sam - nice name for a hamster :) 

xeno - never seen that - seen walking on rear 2 legs but never that far.
I've seen bottom dragging on long hairs - ae*e on floor pulling themslves forward with only 2 rear legs - vet say they do this to give themselves a "deep clean". Can be a sign of worms as well.   

Pinky - you left the lens cap of your mind on again.