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Use tee to process a pipe with two or more processes
Tee can be used to split a pipe into multiple streams for one or more process to work it. You can add more " >()" for even more fun.

Read a keypress without echoing it
This shell snippet reads a single keypress from stdin and stores it in the $KEY variable. You do NOT have to press the enter key! The key is NOT echoed to stdout! This is useful for implementing simple text menus in scripts and similar things.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Pick a random line from a file
This is from perldoc -q random.*line, which says: This has a significant advantage in space over reading the whole file in. You can find a proof of this method in The Art of Computer Programming, Volume 2, Section 3.4.2, by Donald E. Knuth. Who am I to argue with Don Knuth?

Draw kernel module dependancy graph.
parse `lsmod' output and pass to `dot' drawing utility then finally pass it to an image viewer

Search for packages, ranked by popularity
This will take the packages matching a given `apt-cache search` query (a collection of AND'd words or regexps) and tell you how popular they are. This is particularly nice for those times you have to figure out which solution to use for e.g. a PDF reader or a VNC client. Substitute "ubuntu.com" for "debian.org" if you want this to use Ubuntu's data instead. Everything else will work perfectly.

Exclude multiple columns using AWK
Print all columns except the 1st and 3rd.

Diff two directories by finding and comparing the md5 checksums of their contents.
Compares the md5 checksums of the contents of two directories, outputting the checksum and filename where any files differ. Shows only the file name, not the full path.

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!

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