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download and unpack tarball without leaving it sitting on your hard drive

get all Amazon cloud (amazonws etc) ipv4 subnets

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Find the ratio between ram usage and swap usage.
it provides the ratio used for the RAM and The SWAP under Linux. When swappiness is high, Swap usage is high. When swappiness is low, Ram usage is high.

list files recursively by size

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

start a tunnel from some machine's port 80 to your local post 2001
now you can acces the website by going to http://localhost:2001/

Lock your KDE4 remotely (via regular KDE lock)
Forgot to lock your computer? Want to lock it via SSH or mobile phone or use it for scheduled lock? TIP: Make a alias for this (e. g. as "lock"). I found some howtos for ugly X11 lock, but this will use regular KDE locking utility. Note that KDE 3 is using utility with another name (I guess with the same argument --forcelock) Tested on Kubuntu 8.10. Stay tuned for remote unlock.

Bitcoin Brainwallet Checksum Calculator
A bitcoin "brainwallet" is a secret passphrase you carry in your brain. The Bitcoin Brainwallet Exponent Calculator is the second of three functions needed to calculate a bitcoin PRIVATE key. Roughly, checksum is the first 8 hex digits of sha256(sha256(0x80+sha256(passphrase))) Note that this is a bash function, which means you have to type its name to invoke it

Encrypt every file in the current directory with 256-bit AES, retaining the original.
The password is stored in the password file, which obviously must be kept secure, encrypted later with gpg, deleted, or whatever you prefer. To decrypt: $ openssl enc -d -aes-256-cbc -salt -in filename.enc -out filename -pass file:/path/to/password-file Alternative ciphers can be used, of course.


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