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Create QR codes from a URL.
QR codes are those funny square 2d bar codes that everyone seems to be pointing their smart phones at. Try the following... $ qrurl http://xkcd.com Then open qr.*.png in your favorite image viewer. Point your the bar code reader on your smart phone at the code, and you'll shortly be reading xkcd on your phone. URLs are not the only thing that can be encoded by QR codes... short texts (to around 2K) can be encoded this way, although this function doesn't do any URL encoding, so unless you want to do that by hand it won't be useful for that.

batch convert Nikon RAW (nef) images to JPG
converts RAW files from a Nikon DSLR to jpg for easy viewing etc. requires ufraw package

find the longest command in your history

analyze traffic remotely over ssh w/ wireshark
This captures traffic on a remote machine with tshark, sends the raw pcap data over the ssh link, and displays it in wireshark. Hitting ctrl+C will stop the capture and unfortunately close your wireshark window. This can be worked-around by passing -c # to tshark to only capture a certain # of packets, or redirecting the data through a named pipe rather than piping directly from ssh to wireshark. I recommend filtering as much as you can in the tshark command to conserve bandwidth. tshark can be replaced with tcpdump thusly: $ ssh root@example.com tcpdump -w - 'port !22' | wireshark -k -i -

A formatting test for David Winterbottom: improving commandlinefu for submitters
Commandlinefu.com is great but has a few bugs when people are submitting new commands: . 1. There is no preview button. This was a minor inconvenience before, but now is a major problem since new commands won't show up to be edited until they have been moderated. . 2. White space in the description field and in the comments is almost completely lost. People resort to using periods in between paragraphs to force a line break. Indentation of code is ridiculous. . 3. Many characters get munged. . 3a. For example, a less than character in the description gets read as an HTML tag and discarded. In order to type a less than, I've had to type "<" (I hope that comes out right). Unfortunately, when re-editing a command, the HTML entity is turned into a literal less than character, which I have to change back by hand before saving. 3b. Some unicode characters work in the description field, but turn into ugly literal HTML strings when put in the sample output or in an additional command using the $ prefix. . For example, here is a unicode character: ❥ $ Here is the same character after a dollar sign: ❥ . 3c. Some unicode characters don't work anywhere. Bizarrely, it appears to be the most commonly needed ones, such as Latin-1 accented characters. Here are some examples, . Bullet: ?, Center dot: ?, Umlaut u: ?. . 4. Here is an example of the greater than, >, and less than,

Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by EVACopy http://evacopy.sourceforge.net

aptitude easter eggs
this is a reference to Antoine de St. Exupery's "The Little Prince"

Send an email from the terminal when job finishes
Might as well include the status code it exited with so you know right away if it failed or not.

See system users

Log the current memory statistics frequently to syslog
Uses logger in a while loop to log memory statistics frequently into the local syslog server.


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