I use this command to select a random movie from my movie collection..

Prepending

env LC_CTYPE=C

fixes a problem with bad bytes in /dev/urandom on Mac OS X

A bash version.

Nobody wants the boss to notice when you're slacking off. This will fill your shell with random data, parts of it highlighted. Note that 'highlight' is the Perl module App::highlight, not "a universal sourcecode to formatted text converter." You'll also need Term::ANSIColor.

Grab 4 bytes from www.random.org over ssl and format them as an integer

works at least in bash. returns integer in range 0-32767. range is not as good, but for lots of cases it's good enough.

Reads 4 bytes from the random device and formats them as unsigned integer between 0 and 2^32-1.

Sends random sounds to your sound card output (e.g. your speaker). Think... You can also run it remotely on another computer using SSH and scare its user!

Sends random beeps to your PC-speaker. Think... You can also run it remotely on another computer using SSH and scare its user! Don't forget to run it on your dedicated hosting server and watch sysadmin's action from data-center's live remote cameras!

Cycles continuously through a string printing each character with a random delay less than 1 second. First parameter is min, 2nd is max. Example: 1 3 means sleep random .1 to .3. Experiment with different values. The 3rd parameter is the string. The sleep will help with battery life/power consumption.

Fans of "The Shining" might get a kick out of this:

Works in sort (GNU coreutils) 7.4, don't know when it was implemented but sometime the last 6 years.

shuf is in the coreutils package

Great idea camocrazed. Another twist would be to display a different man page based on the day of the year. The following will continuously cycle through all man pages:

Splitting on tags in awk is a handy way to parse html.

retrieves the html from a random command line fu page, then finds commands on the page and prints them

alternatively, pipe to bash (add "| bash" to the end) to execute the command (very risky)

edit: had to adjust to properly display the portion that replaces HTML characters (e.g. " -> ")

This is /bin/sh compatible.

2d6 dice:

3 + 6 = 9

If X is 5, it will about a number between 1 and 5 inclusive.

This works in bash and zsh.

If you want between 0 and 4, remove the +1.

You need to have fortune and cowsay installed. It uses a subshell to list cow files in you cow directory (this folder is default for debian based systems, others might use another folder).

you can add it to your .bashrc file to have it great you with something interesting every time you start a new session.

Of course you will have to install Digest::SHA and perl before this will work :)

Maximum length is 43 for SHA256. If you need more, use SHA512 or the hexadecimal form: sha256_hex()