Normal dropbox behavior keeps a copy on every computer.
Ah, you mean by using some app or daemon. I excluded that possibility because on at least one of my laptops I'm not allowed to install anything, so for me "normal" behavior is using Dropbox as a container for files to download when needed.
And maybe you could write a small shell script to keep that particular file up to date?
Also the one program I've used that opens keepass files directly from dropbox servers keeps a local copy.
Ah, you mean by using some app or daemon. I excluded that possibility because on at least one of my laptops I'm not allowed to install anything, so for me "normal" behavior is using Dropbox as a container for files to download when needed.