No can't say I have but then I don't really do anything that requires specialist tools. I'm sure it happens though.
On the subject of tools reminds me of a mate of mine whos a mechanic. Last year at a boot sale he bought a load of Snap On tools which were broken. He got brand new replacements for them as Snap On tools have a life time guarantee, no questions asked. He paid £10 for a pretty big box and reckons the replacement sockets etc were worth at least £400.
Bit of a bargain there I think.