check out this link:
to get to "THE TERMINAL" go to Utilities > Terminal and open it. It will look like the matrix, that's ok!
Basically, enter this in your terminal window:
ln -s "PATH TO FILE OUTSIDE OF DROPBOX" "PATH TO DROPBOX (which is usually ~/Dropbox)"
On my computer for instance, to sync a folder on my desktop using dropbox, I would type in:
ln -s ~/Desktop/this_file_lives_outside_dropbox ~/Dropbox
Make sure to include a single space between the two paths
"~" means "your user name"
typing ~/Desktop is exactly the same as typing /Users/chris/Desktop (when I'm logged in as "chris")
Some possible fun uses of this trick:
• Sync your Google Earth "library" between computers
(~/Library/Application Support/Google Earth)
• Sync your EXS instruments between computers
(~/Library/Application Support/Logic/Sampler Instruments)
• and so on!