Maybe not THE strangest, but definitely in my top ten:

I was drizzling chocolate on some acetate at work, then when I lifted the acetate, the chocolate dripped UP. Hard to explain, but just imagine little strands of melted chocolate dripping up and off a plastic sheet. And I couldn't ever find where they went, not on the ceiling or floor or table that I could see. It happens like one out of every 3 times I use the acetate. Only thing I can think is that it's static related.