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Resets your MAC to a random MAC address to make you harder to find.
Next time you are leaching off of someone else's wifi use this command before you start your bittorrent ...for legitimate files only of course. It creates a hexidecimal string using md5sum from the first few lines of /dev/urandom and splices it into the proper MAC address format. Then it changes your MAC and resets your wireless (wlan0:0).

Turn On/Off Keyboard LEDs via commandline
Usefull as a light blink to remember events, mails, intrusions, etc... yet another output Since nobody ever uses the scroll lock function... Usefull to interface a linux system with some hardware, for example, opto interfacing the keyboard led to a relay to remotely reset, etc. ( a simple LDR glued over the LED will do the trick ) xset led 3 turns on the third led, ie, Scroll lock xset -led 3 turns it off xset led 1 turns on Numerical Lock led ( doesn t work on all computer ) xset led 2 turns on Caps Lock led ( idem ) Using it as a reset watchdog, the relay expected light pulses. Shall the computer hangs, the relay releases and reset the machine ( discharge of a capacitor ) ;-)

Count TCP States From Netstat
Counts TCP states from Netstat and displays in an ordered list.

List the binaries installed by a Debian package
This shell function displays a list of binaries contained in an installed package; works on Debian based Linux distributions.

Know which modules are loaded on an Apache server
This let you know which modules has loaded the Apache server, very useful to know if the mod_rewrite is ready to use.

change dinosaur poop into gold
if firefox is running the database is locked, so you need to copy the places.sqlite file temporarily somewhere to be able to query it...

Tell what is encoded in a float, given its HEX bytes
It handles all possible combination of the hex bytes, including NaNs, Infinities, Normalized and Subnormal Numbers... $ This crazy DC stuff spent me a few days to write, optimize, polish and squeeze so that it works within the tight 255 character bound... $ You can modify it easily for other IEEE754 numbers, say, half, double, double-extended, quadruple $ (I hope someone will find this useful and submit more dc code to commandlinefu!)

detect partitions
Shows all block devices in a tree with descruptions of what they are.

Check if the LHC has destroyed the world
This says if the LHC has destroyed the world. Run it in a loop to monitor the state of Earth. Might not work reliable, if the world has actually been destroyed.

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.


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