Change account on Linux Dropbox?
Go to dropbox account at https://www.dropbox.com
Security tab: unlink machine.
After that you can restart dropbox at linux machine - it will ask to link again.
killall dropbox
~/.dropbox-dist/dropboxd
The easiest way is probably just to rename the dropbox folders:
killall dropbox
mv ~/Dropbox ~/Dropbox-user1
mv ~/.dropbox ~/.dropbox-user1
Then restart dropbox and set up the new account.
Then you could have a small script that switched between the two by stopping, renameing and starting dropbox.