Currently there is no way to drop files, or list what files are available, on a special remote.
It would be good if "git annex drop" and "git annex find" supported the --from argument.

> I agree, drop should support --from.
>> [[done]] --[[Joey]] 
> 
> To find files *believed* to be present in a given remote, use
> `git annex find --in remote`
> Note that it might show out of date info, since it does not actually go
> check the current contents of the remote. The only reason to support
> `find --from` would be to always check, but I don't think that's needed.
> --[[Joey]] 

For commands that don't support the --from argument, it would also be nice to print an error.
Currently running "git annex drop --from usbdrive" doesn't behave as hoped and instead drops
all content from the local annex.

> This is done now. --[[Joey]]