Danger in Plain Sight (3.5e Maneuver)

''There was nothing in this room but harmless pots. But one pot moved behind you to attack!''

You conceal yourself in shadowy illusions, making you look like any pre-existing item in line of sight that is one size larger or smaller than yourself. For example you can transform into an urn, or a treasure chest, or a statue. When you initiate this maneuver make a Hide check, the result being your effective Disguise check to appear as the item. You remain in this state until you perform any attack that would negate invisibility or any effect which requires concentration (such as spellcasting). You can move, but the object will appear gliding across the ground and quickly break the disguise. If a creature interacts with the false object they get a Will save (DC 15 + Wis modifier) to disbelieve the illusion. True seeing also can defeat the illusion.

Swordsages often use this to get the one-up on the enemy, or as a way of hiding when they are on the run. This is a supernatural maneuver.