Go down to the woods in the summer at dusk where there are A LOT of fireflies (preferably in a white dress, it will show up better). Use a tripod and preset the camera to take a photo with a long shutter speed. Stand in front (DON'T blink) and VOILA.
You're in the middle of an enchanted forest.
I bet if you get creative there are a million other special effects you can pull off playing around with the shutter speed.