Reports are coming in that people visiting http://discussions.apple.com have been seeing the cryptic message "for fun, by tojen" rather than the index of discussion forums they were expecting.
We've managed to reproduce this here at TUAW, but only haphazardly. I saw it earlier in Safari under OS X, but since clearing my cache I cannot reproduce it. Firefox doesn't do it, but lynx (a command line browser) on my Linux server does. Steve Sande has seen it under Safari but not on his iPad. Other people have reported seeing it on their iPhones.
This mixture of affected devices and operating systems that show the message suggest it is neither an OS X nor a Safari hack of any kind. If you have seen it, your computer has not been compromised. Rather, it's something server-side; either on Apple's servers themselv