Misumena vatia

If you are a fly or a bee and you are landing on the wrong flower, the last thing you can see will be something like this:

It's a spider that can rapidly change colour to be absolutely invisible and instead of spinning a web he will just wait. It can catch preys way bigger than him as in this photo I took long time ago in Sicily. And don't tell me it's scary because it is only few millimeters big :)