I trick with ketchup. Last year, kids went crazy. This year, I almost made one cry and I felt really bad.
Anyway, I recommend a fog machine. Wind can ruin it, but I just let it rip with a clamp on the button. I ended up smoking out the block with an eerie haze that called kids over. I still had poor turnout. I always mean to stroll around myself and see if it's my block or the town that's light, but I'm always too busy heckling kids at my door.