The Desktop Exchange Service
The DXS allows for upload and download of very customised information. For instance, an upload call would include the data file, its preview and its meta information in one file, whereas a download list request could be generated based on various parameters such as time of last modification, popularity, data type and more.
Software and Design
An implementation exists based on SOAP::Lite. It started out as DXS-Perl but has subsequently (February 2007) been merged into Hotstuff.