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Load average + API google chart
limite = threshold

Generate SSH public key from the private key

Press ctrl+r in a bash shell and type a few letters of a previous command
In the sample output, I pressed ctrl+r and typed the letters las. I can't imagine how much typing this has saved me.

Display current time in requested time zones.
The time zone names come from the tz database which is usually found at /usr/share/zoneinfo.

Remove invalid host keys from ~/.ssh/known_hosts
Useful if you have to tunnel ssh through a local port and it complains of the host key being different. Much easier than manually editing the file.

Adjust gamma so monitor doesn't mess up your body's clock
[UPDATE: Now works for multiple connected outputs] I woke up around midnight with an urge to do some late night hacking, but I didn't want a bright monitor screwing up my body's circadian rhythm. I've heard that at night blue (short wavelength) lights are particularly bad for your diurnal clock. That may be a bunch of hooey, but it is true that redder (longer wavelength) colors are easier on my eyes at night. This command makes the screen dimmer and adjusts the gamma curves to improve contrast, particularly darkening blues and greens (Rɣ=2, Gɣ=3, Bɣ=4). To reset your screen to normal, you can run this command: $ xrandr | sed -n 's/ connected.*//p' | xargs -n1 -tri xrandr --output {} --brightness 1 --gamma 1:1:1 or, more briefly, $ xgamma -g 1 Note: The sed part is fragile and wrong. I'm doing it this way because of a misfeature in xrandr(1), which requires an output be specified but has no programmatic way of querying available outputs. Someone needs to patch up xrandr to be shell script friendly or at least add virtual outputs named "PRIMARY" and "ALL". . Todo: Screen should dim (gradually) at sunset and brighten at sunrise. I think this could be done with a self-resubmitting at job, but I'm running into the commandlinefu 127 character limit just getting the sunrise time: $ wget http://aa.usno.navy.mil/cgi-bin/aa_pap.pl --post-data=$(date "+xxy=%Y&xxm=%m&xxd=%d")"&st=WA&place=Seattle" -q -O- | sed -rn 's/\W*Sunrise\W*(.*)/\1/p' I hope some clever hacker comes up with a command line interface to Google's "OneBox", since the correct time shows up as the first hit when googling for "sunrise:cityname". . [Thank you to @flatcap for the sed improvement, which is much better than the head|tail|cut silliness I had before. And thank you to @braunmagrin for pointing out that the "connected" output may not be on the second line.]

Generate pretty secure random passwords
These are my favourite switches on pwgen: -B Don't include ambiguous characters in the password -n Include at least one number in the password -y Include at least one special symbol in the password -c Include at least one capital letter in the password It just works! Add a number to set password length, add another to set how many password to output. Example: pwgen -Bnyc 12 20 this will output 20 password of 12 chars length.

Create MySQL-Dump, copy db to other Server and upload the db.
This option makes a copy of your current db and via ssh it transfer to the server you specify and upload the database to the specific User & Password you specify (Note the db User & Pass, can be different from the one you use in the other server) If you are going to use "localhost" as your main db remove (-h) and youst add "localhost"

List folders containing only PNGs

FInd the 10 biggest files taking up disk space


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