[nextgen-gallery] Sharing Galleries Multi-Site

Would be curious if someone (or the author) has written (or is considering writing) a method for pictures to be uploaded in a WordPress MU top-level site and shared with the sub-domains – or visa versa – pictures uploaded to the sub-domains can be combined to be shown in the top level site? I could use this feature today and was going to ask if it exists before I write it.