Create a theme to share with other users on multisite

There is theme I have uploaded on my blog that I am editing, adding widgets, etc. After I am done I would like to save what I have done so that it can be a template/theme that is used by other users on my multisite. Is there a way to save it and share it.

For Joomla users you will know what I am talking about. With Joomla you can do all kinds of edits on a template and then rename it and you could them download it and share with other Joomla users.