This is a 3D model of a ruined cathedral section that I have created to use as a base for one of my flying miniatures, for a table top war game that I play.
Simply print out the ruin, stick it on a base, and insert a 4mm steel rod into the hole. I have magnetized my minature and done away with the stock clear rod, and clear base combination, since in my experience they always snap off/ get scratched anyway. I use a 3/16" (4.7mm) diameter magnet glued to the bottom of my miniature in order to get the metal rod to magnetize well enough for everyday game play. The magnets can be found here: http://www.kjmagnetics.com/proddetail.asp?prod=D31-N52