I think cloud dev ENV is the future, (You don't have to save your file on your laptop or dropbox, you got a Linux runing in the cloud(in c9.io, it's ubuntu 64 bit), and you can see your project running in the cloud.The most exciting thing is you can add your friends then coding/hacking together.)
Ex. I was at an old client's office catching up and a potential user (large agency) fell into the discussion and expressed an interest in my application. He liked it but wanted to see a few additional metrics, that while stored in the database, were not available in the view. I Jumped on a nearby laptop and added it for him in 5min.
His agency is currently in the beta. (probably would've still joined without things going down this way but you get the point)