I want to find or assemble (and maintain) a list of these P2P marketplaces and some information about them, such as what their marketplace is (cars, tasks, etc.), what locations they serve, where they are headquartered, etc.

Why? Because I am personally interested and I know others are as well. A list like this would be helpful to companies, users, other stakeholders, journalists, bloggers, students, law makers, etc.

In case there is no existing list of P2P Marketplaces, I've created this Google Doc and have started adding some information: https://docs.google.com/spreadsheet/ccc?key=0AojDSItu62isdFFZV0VmSTZMTmFOcHBsckdjb3p0LVE . Please check it out and add (or correct) any information you can.

Thank you, Chris

PS: Since I've gotten the question before, I'll pre-answer it now:

The reason I call them "P2P Marketplaces" as opposed to "collaborative consumption" this or "sharing economy" that is that the companies I am interested in for this particular list are ones that:

1) create and facilitate orderly marketplaces, 2) between people, 3) and the people exchange with each other for money (not sharing or bartering).

Regarding the term "collaboration": In my mind, it doesn't fit quite right. To me, "collaborating" is more about individuals (or groups) coming together to create something, such as to a work product or school assignment or art work or musical performance or whatever.

Regarding the term "consumption": I doesn't fit either, IMHO. Plus, I just don't particularly like the words "consumption" or "consumerism" or even "consumer". I like "people" and "person" and "person-to-person." :)