Combine JS and CSS for WordPress admin

I am using W3 total cache which allows me to combine JS and CSS in the forward facing site, but is there any way I can do the same for the admin/backend/dashboard area. I can’t think of a technical reason why it couldn’t be done but I haven’t seen a plugin or code snippit that seems to cover it. At the moment I have 13 scripts and 18 stylesheets the culprits I think being theme and plugin from envato which my client wants, and really the backend is pretty slow even though the cache plugin has the front end reasonably respectable.