Well one I picked up from work is using some kind of cordage or tape and a plastic spoon to make a tool that can hold up a t-shirt easily to rope, or to an air vent.

All you do is break the spoon in half, and then using something to hold the two together secure the two halves tightly. You then use the scoop end, and the very top (non broken ends together, secured) to hold things up. I'll try to get some photos up later.