I re-used the motorized bicycle mechanism I made a couple of years ago to make the ghosts move. If you want to do this too it makes it a more ambitious project but you will have the coolest Halloween display on the block!
Step 1: What you need
Large clear plastic jars with screw lids, for example a large peanut butter jar. Suitable jars are shown in the photo.
White bedsheets, tablecloths, etc.
Battery powered LED puck lights (2 per ghost). The ones I got at Dollarama are much brighter than the ones I got at another dollar store.
Clear monofilament fishing line (I used the thickest, 40 lb test)
White string to tie the neck of the ghost. You can use the fishing line instead, but it's harder to tie.
Washers, buttons, or beads (2 per ghost)
Drill, and a small drill bit (1/16")
And if you want to build the bicycle mechanism, see my previous instructable. Materials required for that are:
1 bicycle. A 10-speed bicycle is best, so you can adjust the operating speed.
1 small electric motor. The one I used came from an 8" floppy disk drive. Any small motor from a hand-held power tool, fan, etc. will do.
Assorted scraps of wood. Some pieces of 2x4 and a big piece of chipboard (counter-top material) are what I used.
Small pulleys. I used 7 of these in my setup..