Terminal in full screen mode: how do I recover from "cat /dev/random"
If you have Terminal.app open anyway (doesn't matter whether it's in fullscreen mode or not):


Cmd-T to create new tab/shell
ps aux | fgrep /dev/random to find the running cat (you can grep for cat as well but there might be more than one matching line)
kill &lt;PID from above&gt; (or kill -9 &lt;PID&gt;)


Just be patient, the system may be really slow (even on a multicore system as I've just found out).