If you haven’t seen it:
http://www.kickstarter.com/projects/bushing/openvizsla-open-source-usb-protocol-analyzer
You can “pledge” some money and based on the amount you can get the device in one form or another when it is done.
Can you say ‘vaporware’? This sounds like the same scheme often used back in the 70’s in the back of electronics magazines. Some outfit would run an add for a new product at a good price and then use the money they got in ‘orders’ to actually fund the development of the project.
I don’t think so. This site is for funding projects, not for taking orders for future products. Some projects offer something back based on the amount of your support, some just give you big “thank you”. 
I guess there is a risk that a project will stall too.
What is interesting is that this particular project got more than 400% of what has been asked for, shows the level of interest in that particular device.