This site may damage your computer. Yeh, this one right here.
I suppose if you were to cut and paste the examples of WTFs and compile and run them it just might, but I think it would be better if it had said "This site may damage your sanity".
TRWTF, of course, is the notion of a cheese wedding cake. WTF!?!
Refreshing makes the warnings appear and disappear. Maybe part of Google's internal content caching network got disconnected from the URL scanning service and choose to fail in a CYA mode?