Web Service Development Utilities
Here are some tools that I have found helpful for developing and debugging web-services:
Web Service Studio
A excellent soap client, If you are creating/consuming web services and want to play with them without creating a client, this is a great tool. I use this one all day long.
HTTP Fiddler
Lunch this little app and it registers itself as the default HTTP proxy, allowing you to look into all HTTP traffic. This tool allows you to view the header and the HTTP data as text, hex, images or XML. Also the option of replaying HTTP requests is really useful.
XMLSpy
If you work with XML, you should be using this tool. Whether for schema design, XML file viewing, creating your own WSDLs or trying out different Xpaths, this is the tool.
WSCF
We all know that the proxies generated by visual studio's Add Web Reference are not as good as they could be. And also that the [WebService] attribute encourages RPC like design of your services. This tool enables contract first based design and acts as a code generator from wsdl, generating proxies that are far more useful than the vs net ones(public properties, collections, serialize classes, et.c.)
Here are also some tools I have been meaning to try out, but haven't found the time to do so.
SoapScope
I downloaded this tool some while ago, and it seems to work like fiddler in that it acts as a proxy, allowing you to view your ws calls, and also validates them for basic profile support. It also acts as a client allowing you to generate requests from wsdl.
WSI-BP test tools
Of course we all should test our services for Basic Profile compliance, this might be obsolete if SoapScope does this well (I think it uses these tools internally)
WSDigger
This tool from McAfee allows you to inspect your services for security, both for WS-Security and injection attach (SQL injection, cross site scripting and xpath injections)
Are there any other tools out there I should be aware of ? What are you guys using ?