I spend a lot of time worrying about the privacy implications of the new wave of information about people that's becoming available, but I'm also fascinated by the beneficial possibilities. Rapportive and Etacts are great examples of that, using public profile data in innovative ways to solve every day problems.
What's less well-known is that they're both built on top of the Rapleaf API. Rapleaf has traditionally been focused on B2B applications, and any firm selling personal information to other companies is going to suffer from an 'ick' factor, but the new startups demonstrate that a 'phone book for the internet' can offer some practical benefits to users too.
I sat down with Auren and Dayo from Rapleaf on Friday and had a wide-ranging discussion about this world. They're very careful not to steal any of their partners' thunder by trumpeting the connection, are in the habit of keeping a low profile generally and so probably wouldn't want me to blog about this, but I think their API is a massively under-used resource in the startup world. If you're doing anything with sets of email addresses, you can offer your users much richer views of the people behind those addresses using Rapleaf. It's not perfectly accurate in the connections it finds, but it does a pretty good job and if you need an example of how to implement it, you can find one here in my FindByEmail project.
Just remember, this is personal information about real people you're dealing with, so use it for the forces of good, not evil! And if you want to remove your information entirely from Rapleaf, you can do that here.