Mac OSX has this feature called (I think) 'Services'. It is available in the menu bar under the filename of the application (e.g. Finder) and then selecting 'Services'. This gives you access to a list of applications that provide 'services'. For example, if you are browsing a website with firefox and you have some text selected on the page, the services list has an entry for Mail > send selection
.
I've been using a Mac for almost 3 years and I've literally never used it (but I've known it to be there from the beginning).
So, is it worth for an application developer to provide support for this (i.e. provide some services actions)? Or would it be a waste of effort (because no one, or very few people, uses it) ?