Sounds like you aren't working with drop ceilings, correct? Because if you are, you could rig to a scissor clamp and grip head, or (carefully) bite to something above the panels.
But if you've got a regular ceiling, I can think of two options:
Most Kino units have little gold eyelets for screwing into ceilings. If the place you're shooting at will let you put holes in their walls, this is a solid option. Be sure to screw into as many set of beams as you can and use dry-wall anchors where you can't. Test the weight before you put actors underneath.
The other way is to remove the guts from the backing and tape it. Take out all the bulbs and header cable and use paper tape (perhaps on each individual bulb) to keep them up. To control spill, take some duvateen and tape it in a rectangular shape around the bulbs, creating a skirt.
And if neither of those works, use china balls!
Let us know how it goes!
EDIT - And somehow I missed that there are already a million replies to this thread. My work here is done.
Edited by Matt Hingstman, 25 April 2011 - 11:29 PM.