Dropbox is the easiest way to store, sync, and, share files online. There’s no complicated interface to learn. Dropbox works seamlessly with your operating system and automatically makes sure your files are up-to-date. Available for Windows, Mac, and Linux.
I’ve been a customer now for over a year, and its become a vital tool for me as I manage life between my work-tower and my home-tower. Now that there is an iPhone app, I think I’ll still keep it, even as I move to a one laptop system.
From a business perspective I also have to say: Dropbox does it right. Great concept, great technology, pacing themselves while growing and improving steadily.
I encourage you to go get a free account and try it for yourself.