Geni is taking off — it allows you to input your family tree, or to the extent that you know. Then other family members can continue — adding to it, which then branches into other families, whom then are alerted, and on and on. You get the picture — the web application is viral as all hell.
I was trying to think if there’s something else that could possibly take-off like this — something where you add to the extent of your knowledge, then those people continue adding to the extent of their knowledge, etc.
Is there a possibility with housing? I still think it’s ridiculous that in most apartment complexes, neighborhoods, etc, people don’t know their neighbors. What if there was a site where you specified where people lived? I’d specify where my family all live and my friends — then hand it over to them; they’d add their family and friends. Eventually, you have this big database / map of where people live — and their degrees of separation.
“Steve, aren’t you talking about the phone book?” Well, yes and no. Yes, addresses of people. But more particularly, how those people all relate to you.
Obviously some privacy issues would need to be worked out: Would I want random strangers to know who I am and where I live? Or, would I be OK with them knowing where I live, but not my name — rather just my MySpace URL? Or maybe random strangers would know that I live within .5, 1, 2, 5 miles from a specific address — maybe, specifically their address (so that they couldn’t test tons of addresses to narrow-down where I actually live).
If you join via someone else adding you to the map, then you may see their friends/family mapped out (likely the “vicinity” idea) — and you can click on them to learn more about them. Everyone can get more detailed on their profiles and then eventually conduct searches to find people in your vicinity that… like to bike ride, or like to roller blade, or like to play Monopoly, or like to drink wine, etc. There’d eventually be virtual “bulletin boards” — where you could post things for sale, garage sales, etc. People that live in a specific apartment community or building, could discuss the community/building — discuss changes they’d like to see, etc.
Monetization: If this was a Google Maps mashup, you could also put various retailers on the map — i.e. Starbucks locations, McDonalds, etc — and charge them for being listed. Advertising could be done on all pages of the site. Also, you’d know a bit about your users (specifically where they live), so you could drive targeted local advertising to them — such as restaurant offers, notifications of upcoming events or conferences, etc.