According to ABC News, a US congressman was suprised when this photo (right) appeared in his Twitter stream.
The theory is that someone hacked into his yfrog account and posted the photo without the account holder's knowledge. To do this all someone would need is the email address associated with the account.
Yfrog's email posting service is currently down, one can guess because they have detected this security threat. But with all the cool Twitter apps around, it poses the question: How safe is your Twitter account?
-Susanna (A Modern Mother)