There is already a fair crowdfunding scheme for science called "taxes".
I feel the increase of popularity of crowdfunding schemes for science or health care is detrimental to the cause. They will never be able to approach the same level of funding that a state can give away, yet they will be a good excuse for the politics to reduce the amount of money spent on these issues: "The crowdfunding schemes are already taking care of it, aren't they? Why should we waste taxpayers' money? If prof. X wants its experiment to be funded why doesn't it ask for money on indiegogo?"
For those who may thing "nobody is going to ever suggest that", well, the current government of UK as been elected exactly on this promise: http://en.wikipedia.org/wiki/Big_Society
You should consider the proposition that funding science with taxes is a great excuse to politicize science. Moreover, the notion that science funding could ever be objectively "fair" is complete hokum, and the idea that a political apparatus could find a particularly fair solution is even crazier.
Of course, I have to disclaim that I ran a successful science crowdfunding campaign (http://pledge.indysci.org). As to why it couldn't be funded by taxes, it's because the NIH coordinator for the subsection working in the division that would have funded it used to lead the project I'm continuing so there's a conflict of interest.
Now, this is a relatively 'boring' and particularly coincidental reason for the inability for taxpayers to be able to fund this project. Usually the real reasons are internecine conflicts within sciences competing for funds, personal differences, political connections, etc. Consider for example the case of Leo Paquette, who denied funding to a group and then turned around and stole the idea for himself. (ScienceWeek. 1998-03-20) Of course the system came to a settlement whereby Paquette got a slap on the wrist (agreed to not accept funding for 2 years) instead of kicking him out.
My personal opinion is that if people want to say they fXing love science, then they should be willing to reach into their wallets and pay for it themselves. Science has a clear social benefit and to that end, everyone should want to help out. Forcing other people to pay to make you feel like you have chipped in yourself - is just patting yourself on your own back for making zero personal sacrifice.
There's also already a crowdfunding scheme called "the private market". So far its existence has not caused governments to stop funding science.
The way I see it is that each of these schemes allows money to be allocated according to different sets of criteria, each of which we hope will overlap with the vaguely understood criterion "benefits society". Since the overlap isn't perfect (sometimes pathologically so), I'd argue that diversity of crowdfunding schemes is a good thing.
There is already a fair crowdfunding scheme for science called "taxes".
I feel the increase of popularity of crowdfunding schemes for science or health care is detrimental to the cause. They will never be able to approach the same level of funding that a state can give away, yet they will be a good excuse for the politics to reduce the amount of money spent on these issues: "The crowdfunding schemes are already taking care of it, aren't they? Why should we waste taxpayers' money? If prof. X wants its experiment to be funded why doesn't it ask for money on indiegogo?"
For those who may thing "nobody is going to ever suggest that", well, the current government of UK as been elected exactly on this promise: http://en.wikipedia.org/wiki/Big_Society