Hi Dave
The Louis Vuitton shop in Edinburgh (yes, of course I'm in there every day

) has a brilliant window display just now of large foil letter balloons spelling out the name of the shop and they are tied through the loop with curling ribbon and weighted with real sparkly shoes. The catch is, the letters are actually air filled, I'd guess, because they are secured via rods to the back wall of the window, if you know what I mean. Therefore, the letter with the tether and the shoe all appear to be floating, each at different heights. It's a very nice, eye catching effect, but obviously you'd want to do your own thing.
How about air filling large (16"+) round latex balloons and suspending them from the ceiling using strong monofilament (25lb test), with some curling ribbon attached to the neck and a shoe attached as a 'weight'.
I know this probably isn't what you were looking for when you asked for suggestions, but thought I'd mention it anyway, just in case it gave you any ideas...
Hope it helps
--Neil