I know that some people have the opinion that Dropbox is not as secure as it claims, but I’ve read up on the issues, and am really not that concerned, for the uses I am going to put it to. Being mainly a quick and easy way to dump photos/videos off of my smartphone and netbook when I am travelling, so I don’t have to worry about memory.
Very easy to set up (I have it running on an HTC phone, two Windows computers and a Linux netbook) – you have a folder, which you can position anywhere – in your documents or on your desktop, which Dropbox monitors. Any files changing in that folder are transferred to your online repository at Dropbox, and within minutes are grabbed by Dropbox installations running on any of your other devices.
What I particularly liked was although Dropbox installs to run automatically on startup, this is easily changed in preferences – which addresses issues I have with the idea of your computer’s resources being nibbled away by constantly running but only occassionally used services. You can also set it to only syncronise certain subfolders – hence my netbook (with limited SSD “diskspace”) only balances to a single folder dedicated to it, allowing me to dump stuff off it easily onto my main computer, but not grabbing everything in my whole Dropbox.
In particular, my phone is well-integrated into Dropbox (and was the reason I started looking at it), in that any photos/videos taken now get transferred immediately and automatically to my Dropbox account, allowing me to delete them from my phone. It was amazing to see the speed that they appeared on my desktop.