I love this idea! And I espeically like your suggestion for people to comment on what they think it is. It will be fun to see how many people actually guess it right, and what odd things people think it is.
Way back when I used my old Canon 35mm with a Macro Lens and took shots all around the house. Then I would pass the photos around and see how many folks could guess. It was a blast and people were amazed how little they actually saw around them.
Games Magazine has been doing this for 20 years as the "Eyeball Benders" game. They print a couple of pages of super-close macros of strangely shaped, brightly colored objects that are sometimes laughably easy to identify (like the teeth on a comb) and often impossible. Every time I take a close-in macro shot I'm aiming for an "eyeball bender" and I almost never get one! This would be a really fun challenge. :)
Actually, I get really fed up when people judge a photograph (read - macro) on how identifiable the object is without thinking about lines, shapes, textures, composition and so on. This type of thinking merely reduces the scope of photography. In my last few shots, I've been trying to ignore the object and concentrate on how the inherent shapes can be used to create an art work. (end of rant...)
