We love Dropbox at Daemon. We've finally got rid of the file server in the corner and rely on the Dropbox service for all our internal storage. recently we've started building web applications that can be dynamically updated by just copying files into a Dropbox share -- clients love it! Key to this is getting Dropbox set up as a service on your server.
We've set up Dropbox as a Windows service on several servers via these instructions:
The important thing to note is that Dropbox cannot run on the desktop and as a service at the same time. If you need to launch the Dropbox application (such as to change the config settings) you must stop the service first and restart it again after you've exited the system tray application. We must also keep "Show desktop notifications" and "Start Dropbox on system startup" DISABLED for the service to work.