Alot of people speak about this and my brother in law did it, it's a first implementation of his WSE filter. From a guy that was coding only in c++ and Java he moved to .NET and started a new software comapny. He does magic.
Adding a zip filter to web services
Passing large amount of data through web services can become a hugh bottle-neck in WAN application architecture ( i.e server is on the web ), and in any case a real load on the network traffic, this is one solution for downsizing the network costs