Apparently you can use Javascript to copy to the system clipboard. Don’t know if this works on non-Windows systems, but certainly, Internet Explorer seems to support it.

I’m sure that there must be a security risk here – but I haven’t really thought about it yet. And certainly, it appears that Mozilla agree that there is a security issue as it works another way, as shown at Krikkit.net. In short, you have to sign your code or drop your security level…