mled is a program that translates stdin to morsecode and uses your CAPS LOCK LED to display it.
$ echo "sos" | sudo ./mled
At the moment it mled only supports ascii-characters A-Za-z0-9.
You can also abuse it as a binary clock with the -t switch.
- ThinkPad X-Series
- TypeMatrix 2030 (tested by maximeh)
- hp nx7010 (winks)