Yes, I got the idea from all the sites that do it using Javascript, but I wanted to post the example to ##security, and half of the people there probably has the browser set to "block JS by default" :D
Definitely, I didn't even know that command :D - but I had to `apt-get install sl` on my machine first. Maybe just do a telnet to a nonstandard port on my server and then send special characters to do the animation? That could work...
I always install sl because it helps me. If I'm frustrated from typing too quickly/angrily to even get "ls" right, the little train breaks me out of my fugue state and I have to laugh and shout "choo choo!" in the office :D