In Ubuntu 11.04 I used InSSIDer to scan the available APs and sort them by signal strength.
Unfortunately the program seems to be broken in Ubuntu 11.10, and
iwlist wlan0 scan
doesn't return anything meaningful.
What options do I have to scan for available Wireless Access Point, possibly with a GUI?
sudo iwlist wlan0 scanning | egrep 'Cell |Encryption|Quality|Last beacon|ESSID' should help.
It's the combination of sudo (run as root, do privileged operations), iwlist wlan0 scanning (produce some output on STDOUT), the pipe symbol "|" (connecting STDOUT of the command(s) to the left to the STDIN of the process on the right), and an egrep command with a "single quoted" (to prevent the shell from interpreting the "|" characters) Regular Expression to filter STDIN. See man bash, man sudo, man iwlist, man egrep, and man re_format for details.
ALWAYS do man whatever (as above) BEFORE you execute a command string from someone else. Self-education is much safer than blind trust.
