Hey, do you remember sometime back I was searching for some CAML tools.
I think I have found them.
Patrick's got one at U2U and Stramit's got one too.
btw, Patrick, I think you need to mention that CAML testing will only work on the same box as SharePoint is installed on. Same problem on my tool (because it uses the SP API, not the WebServices), but I am sure we SP Devs dont mind ;)
Stramit's blog posting has some other cool tools as well.