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Manually Pause/Unpause Firefox Process with POSIX-Signals
Continue with: $killall -CONT -m firefox Suspends all Firefox Threads. Results in Zero CPU load. Useful when having 100+ Tabs open and you temporarily need the power elsewhere. Be careful - might produce RACE CONDITIONS or LOCKUPS in other processes or FF itself. matching is case sensitive.

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

ThePirateBay.org torrent search
This one-liner greps first 30 direct URLs for .torrent files matching your search querry, ordered by number of seeds (descending; determined by the second number after your querry, in this case 7; for other options just check the site via your favorite web-browser). You don't have to care about grepping the torrent names as well, because they are already included in the .torrent URL (except for spaces and some other characters replaced by underscores, but still human-readable). Be sure to have some http://isup.me/ macro handy (someone often kicks the ethernet cables out of their servers ;) ). I've also coded a more user-friendly ash (should be BASH compatible) script, which also lists the total size of download and number of seeds/peers (available at http://saironiq.blogspot.com/2011/04/my-shell-scripts-4-thepiratebayorg.html - may need some tweaking, as it was written for a router running OpenWrt and transmission). Happy downloading!

continuously print string as if being entered from the keyboard
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. $ cycle 1 3 $(openssl rand 100 | xxd -p) Fans of "The Shining" might get a kick out of this: $ cycle 1 4 ' All work and no play makes Jack a dull boy.'

combining streams
2>&1 permit to combinate stdout and stderr. grep will catch stderr and stdout instead of stdout only.

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Check to make sure the whois nameservers match the nameserver records from the nameservers themselves
Change the $domain variable to whichever domain you wish to query. Works with the majority of whois info; for some that won't, you may have to compromise: domain=google.com; for a in $(whois $domain | grep "Domain servers in listed order:" --after 3 | grep -v "Domain servers in listed order:"); do echo ">>> Nameservers for $domain from $a

Binary clock
cryptic version

Extracting a range of pages from a PDF, using GhostScript
In this example we extract pages 14-17

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.


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