Cantilever beam holding object is controlled through changing direction of voltage applied. When the voltage is zero, release the object.

Still, they were just as capable of firing a tractor beam at your brain and holding you in front of the television set as Portal or BioShock.

Michael tells Pope that if he left now, the support beam he's holding would give in and the whole model would collapse. Michael says he has to stay and hold it in place until the glue dries.