Here is another kind which I would have never expected:

The Student:
Someone who whispers you and asks you how you are doing that, so you tell him and point him to the wiki for information (repeatedly). He then asks you which software you are using. 5 minutes later he says "I installed the software, what do I do next?"

I might be willing to babysit a friend through this process but sure as hell not some random guy that whispers me.