Driftnet is a program which sniffs network traffic and picks out images from TCP streams it observes. It is interesting to run it on a host which sees a lot of web traffic.
You can download it from the following link: https://packetstormsecurity.com/files/download/26381/driftnet-0.1.6.tar.gz
Source: https://packetstormsecurity.com/files/26381/driftnet-0.1.6.tar.gz.html