Lately I developed a webservice for one of our customers. One tool which got by during testing was soapUI. This tool really kicks ass because of it's capabilities. And for my dutch collegues: it's free...

Some things you can do with this tool:
- Web Service Inspection
- Web Service Invocation
- Web Service Development & Validation
- Web Service Functional Testing
- Web Service Load Testing
- Web Service Simulation
Go check it out @ http://www.soapui.org/. You got your own SOAP testing tool? Share it in the reactions below.