I have recently uploaded my WSCompression library which compresses web service/SOAP calls. It contains full source code, examples and VS.NET project file. No licencing mumbo jumbo so you can do as you will. Reason I uploaded it, is I mentioned it on the ASPAdvice email lists a little while ago and it generated quite a bit more interest than I had anticipated. So for all those interested, you can grab this library here. To use, just apply the [WSCompression(CompressionLevels.High)] attribute on both web service client/proxy and the service itself, and you are away.
Please make sure you read the README.TXT file before using.