Foreword: I've read the other questions about the Make Money Fast(TM) (like Offering actual money as a bounty?).
The basic idea is to offer money to the site for quick support on a probably complex question. Say I want to be spoon fed on a problem like "How can I compile Eclipse at home?" and I offer $20. Or I have a production problem that costs me $1000/h and my Xyz specialist is sick in hospital.
The money would just buy you a place at the top of all the question pages for a limited time, and it would go directly to SO (so no use to game the system to milk it for money).
Some ideas for details:
Half the money must be paid in advance to open the question (so you can't back out even if you don't get an answer) plus you can set a time limit. If you don't get an answer within the time limit, the money is lost (well, SO is $10 richer).
When I accept an answer, the rest of the money must be paid. Which probably means that I have to pay all the money in advance and SO refunds 50% or all the money must be paid and SO gives a voucher for 50% of it for another question. That would also discourage people to pay half the price by simply not accepting an answer.
I was also thinking about giving twice the reputation for such questions but that's probably not a good idea. The pressure to answer these questions should be to support SO even more. Maybe add a merit badge?
Another idea was to need a certain reputation for this (like the bounty system). But a lot of people who need such assistance don't have the time to build rep. So maybe such questions need moderator approval or maybe the approval of someone with >10K rep.
What am I missing? :-)
[EDIT] I'm aware that SO has no problem to raise money right now. But venture capital has to be paid back eventually and so far, no one has come up with many good ideas to help making money to pay for the traffic we cause.
I've been thinking about this for a long time (like most people here) and this idea seemed to me to be a first step into a direction that isn't altogether wrong. Apart from that, I only see one solution: Ask for donations like the WikiMedia foundation does. Unlike them, SO doesn't even have a product to sell.