Yes, such an idea is viable: http://techcrunch.com/2012/10/19/fundersclub-seed-round/ "...FundersClub wants to radically change startup funding by letting non-VCs invest..."
"For those unfamiliar, FundersClub is a website that picks promising startups and lets people invest in them over the web in return for real equity. Anyone who’s an “accredited investor” (earns over $200,000 a year or has a net worth over $1 million) can browse startups with open rounds ranging from a few hundred thousand to a few million dollars."
"And traffic and investment could explode if the JOBS Act passes, allowing anyone to fund startups through FundersClub, not just accredited investors."
"...there’s a chance it may be violating the Securities Exchange Act of 1934 if it handles money for investors without being a licensed, registered broker dealer..."
"FundersClub firmly believes it’s legal ... It isn’t disclosing details on exactly how the financial back-end works right now, but apparently there’s a reason it hasn’t been shut down."
This article talks about a new website that just came online that basically helps anyone become an Angel Funding source. They find a business, then promote to individual investors to pool money so they can in turn write the big checks as a traditional Angel Funder would.
Yes, definitely. It is called "Stock Exchange".