I use a product called Loctite which is a removable putty used to hang things on walls. I very tiny amount on the feet (see figure laying down) will make a figure stick on just about any surface (like the figure on the left). The nice thing is that it is not permanent and rubs right off and can be used over and over again. So you can easily move figures. You can get it at Walmart in the office supply section. One package would probably do a least a 100 figures. I also use this when I spray paint small parts - I put a small bit on the back of the part and stick it on a sheet of cardboard - I can easily hold the cardboard and the small part does not get blown away by the air pressure of the spray gun.
