When you summon a FallingSand entity which rides a villager and teleport it every game-tick to you, the villager will float above you and bounce down and than will fly above you again and so on...
MC-48106
Entity Teleportation Bug
Resolved
Fixed
0
marcono1234
(Unassigned)
Unconfirmed
Minecraft 14w06b, Minecraft 14w20b
Minecraft 14w29b
Retrieved
Seems to be fixed in 14w29b