I recently discovered a cute little front-end to nmap called zenmap.
Zenmap is installed by default in distributions such as Backtrack Linux, but is also found in Ubuntu’s repositories.
Zenmap offers different types of scans (varying from ‘fast’ to ‘slow comprehensive scan’) but the feature that makes me like Zenmap the most is the topology pane. It builds a map of the internet around you, and displays routes, delays, and host type:
To build the map, suffice to choose a scan method, for example, “quick traceroute” and choose a
victim target server, and launch the command. Zenmap will parse the output and update the map.
Another tool that makes plenty of fun is netdiscover that scan the local network to discover connected device. With it, I discovered that my powered-down, but still connected to the network, Dell R210 responded to netdiscover (probably the Wake-on-LAN interface).