I was thinking on a per torrent basis. The .gitignore format is well known and there are a lot of goot templates on github et al, so using them would be a very convenient way to share github managed directories via your tool.
I think that the glob library I'm using implements the same syntax as `.gitignore`, so it would be easy to add an `--ignore-file PATH` option.
I opened an issue to track this: https://github.com/casey/intermodal/issues/378