Symlinks are a great way to use Dropbox to sync application data that normally is restricted to one Mac. These can be set up in Terminal, but not everyone is comfortable in the command line.
Thankfully, the guys over at Junecloud have put together an Automator actions that make this task as simple as drag and drop. Simply select the folder you want to sync — make sure it’s already on your Dropbox — and then point Automator where the link should go — usually in your ~/Library/Application Support folder.
There is one major limitation to this setup — you can only have the app open on one Mac at a time. That said, for those of us who like our work Macs to be like our homes ones, it’s a great little trick.