Hmm - thanks for the replies.

I am still somewhat unclear how they managed to get my e-mail address just by my being connected to the Internet. Would the fact that Knoppix boots with known passwords mean that you are open to anyone hacking such details if you enter them in one of the Knoppix client applications (eg. a mail program)?

My PC doesn't normally 'leak' e-mail addresses unless it has been compromised. I am trying to suss out the most likely cause of the compromise.

Is the STD version of Knoppix likely to be more secure by default? There's no point in using the CD as a utility disk if it is easily hacked the minute you go online !