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dmesg with colored human-readable dates
Use sed to color the output of a human-readable dmesg output

Remove all unused kernels with apt-get
Note the double space: "...^ii␣␣linux-image-2..." Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel). I'm bummed that this took 228 characters. I'd like to see a simpler version.

Simulate slow network connection locally
Replace 500ms by the desired delay. To remove it: sudo tc qdisc del dev lo root netem delay 500ms

Download all images from a 4chan thread
Useful for ripping wallpaper from 4chan.org/wg

Strace all signals processes based on a name ( The processes already started... ) with bash built-in
Especially for sysadmins when they don't want to waste time to add -p flag on the N processes of a processname. In the old school, you did ; $ pgrep processname and typing strace -f -p 456 -p 678 -p 974... You can add -f argument to the function. That way, the function will deal with pgrep to match the command-line. Example : $ processname -f jrockit

Losslessly rotate videos from your phone by 90 degrees.
Takes all the .3gp files in the directory, rotates them by 90 degrees, and saves them in the lossless ffv1 encoding. If this rotates in the wrong direction, you may want transponse=1 Re-encoding to ffv1 may result in a significant increase in file size, as it is a lossless format. Other applications may not recognize ffv1 if they don't use ffmpeg code. "huffyuv" might be another option for lossless saving of your transformations. The audio may be re-encoded as well, if the encoding used by your 3gp file doesn't work in a avi container.

total percentage of memory use for all processes with a given name
This command will add up RAM usage of all processes whose name contains "java" and output the sum of percentages in HRF. Also, unlike the original #15430, it wont fail on processes with a usage of >9.9%. Pleases note that this command wont work reliably in use cases where a significant portion of processes involved are using less than 0.1% of RAM, because they will be counted as "0", even though a great number of them could add up to significant amounts.

Count the number of deleted files
It does not work without the verbose mode (-v is important)

A DESTRUCTIVE command to render a drive unbootable
THIS COMMAND IS DESTRUCTIVE. That said, lets assume you want to render your boot drive unbootable and reboot your machine. Maybe you want it to boot off the network and kickstart from a boot server for a fresh OS install. Replace /dev/fd0 with the device name of your boot drive and this DESTRUCTIVE command will render your drive unbootable. Your BIOS boot priority should be set to boot from HD first, then LAN.

get all bookmarks from all profiles from firefox
for i in $(ls /home/marco/.mozilla/firefox/*\.*/places.sqlite); do sqlite3 $i "SELECT strftime('%d.%m.%Y %H:%M:%S', dateAdded/1000000, 'unixepoch', 'localtime'),url FROM moz_places, moz_bookmarks WHERE moz_places.id = moz_bookmarks.fk ORDER BY dateAdded;"; done


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