Reward the chain: Incentives for Surveys using Social Media

So here's the thing. All those nice shiny, familiar email addresses we use to send survey notifications are decaying, they are losing value by the moment. I've had an email address since 1984, and very little in my life dates back from then now (well except me that is). A couple of weeks ago my primary email address stopped working (I didn't pay the hosting bill on time). I had a moment of panic and then I realized: it really didn't matter that much. Personal friends are pretty much all on Facebook, business contacts via LinkedIn, anyone who really needs to get to me fast has my mobile number.

Email is so over.

Obviously the next way to get to people for surveys are via mobiles or social networks. It struck me that the usual model of incentives for respondents doesn't fit the social media world very well. We want people to do the survey via social media sites AND pass on the link. There has to be an incentive for the latter to happen, let's be reasonable, people want to get paid for helping.

We need to come up with something that will reward respondents for sending the survey link on to their friends as well as them completing it. How about trying to reward people for reposting based on the number of people they repost to (hard to track I would guess) ? Or if they or someone they repost to is the Nth complete of the survey ? So if you repost the link and you or one of your friends is the 10th, 100th, 1000th et al complete you get money/something ? Maybe report how long your "chain" of completes are ? It would be a sort of survey incentive pyramid scheme. Is anyone doing this ? Anyone have any other ideas ? So far the whole social media and surveys melange has not totally taken off. Viral dissemination is nice, but we need to be able to push to a lot of people....