I love dropbox. It's free unless you wish to use massive amounts of storage, it's simple, and it rewards you for evangelizing it. It's to the latter point that I wish to write on.
I have diligently spread the word about the greatness of dropbox and have risen from 2GB of space, the entry point for new users, to a whopping 10.75 gigs - one referral away from the maximum 11.
Side note: upon reaching the final referral, I have voiced my wishes to dropbox that something magical occurs, involving unicorns.
As I approach the limit of bonus space for dropbox I have come to realize an amazing thing: my dropbox account forms a rather interesting social graph.
First some facts:
* I have successfully referred 46 people to dropbox
* 9 joined but did not complete (by downloading the program)
* 6 were ineligible (their computer was recognized by dropbox)
* 80.8% of my used space is shared with others
* 8 organizations share folders with me
* 23 people share folders with me
Here's the interesting thing about the 23 people -- no two are alike. None of them have any way of discerning how many folders I have in total, and who I share them with. We have a set of files we share, and beyond that it is total darkness.
There's overlaps too. Some of the folders contains groups of people that carry over four out to of the five people -- almost like Google circles or more accurately reflecting the overlap of real-life collaboration -- but again, no two people I share folders with share the exact same folders.
Add to that the sharing the 23 people I share with who share other folders with people I don't know. Or, they share with one or more of the other 22 and not with me!
The greatest part is -- unlike Facebook and other blatantly social applications -- dropbox does not reveal my social network -- even if you're apart of it.
Dropbox is great. And, the world is becoming much more social and collaborative in ways you probably haven't sat down to think of.