I have just managed to get my mac working again after what Skype did to it.
Here's the message I sent them:
"Skype trashed my mac OS X installation
I downloaded Skype for my mac mini which uses mac OS X 10.4.11...
I installed Skype and tried a test call to test my headset.
I got no sound on my headset and clicked the red phone icon in Skype to hang-up and Skype crashed itself and crashed mac OS X and trashed the installation.
I had to wipe my mac's hard drive and re-install mac OS X.
I will not be attempting to use your program again as it is obviously flawed in a major way."
I can't understand how anyone would use such a program when it's so flaky as to cause irrepairable damage to a computer installation.