RadialNet is a network visualization tool developed for Umit during the Google Summer of Code 2007. In Umit it's called UmitMapper. It consists in a graphical tool to illustrate the Nmap network mapping. You can see a video demonstration based on version 0.3 here.
ate-limit all incoming SSH connections to 8 in a one minute window. Normal users will have no trouble logging in, but the brute force attacks will be dropped, limiting the number of possible account combinations from unlimited, to 8.