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Analyse an Apache access log for the most common IP addresses
This uses awk to grab the IP address from each request and then sorts and summarises the top 10.

Backticks are evil
This is a simple example of using proper command nesting using $() over ``. There are a number of advantages of $() over backticks. First, they can be easily nested without escapes: $ program1 $(program2 $(program3 $(program4))) versus $ program1 `program2 \`program3 \`program4\`\`` Second, they're easier to read, then trying to decipher the difference between the backtick and the singlequote: `'. The only drawback $() suffers from is lack of total portability. If your script must be portable to the archaic Bourne shell, or old versions of the C-shell or Korn shell, then backticks are appropriate, otherwise, we should all get into the habit of $(). Your future script maintainers will thank you for producing cleaner code.

List all the files that have been deleted while they were still open.
If your customer deletes a file that is still in use by a process, that space does not get freed up (will not show up in df) until that process either closes the file on its own, or is killed.

Create user add lines from partial passwd file
Handy if you are installing a new server or recovering an old one and you have a passwd file with the accounts you want to add to the server. If you edit the file so that only the accounts that you want to add are left this line will spit out the correct useradd lines. The uid, gecos and shell will be preserved.

Get Futurama quotations from slashdot.org servers
slashdot.org webserver adds an X-Bender or X-Fry HTTP header to every response!

SVN Clean
Removes all unversioned files and folders from an svn repository. Also: $ svn status --no-ignore | grep ^I | awk '{print $2}' | xargs rm -rf will remove those files which svn status ignores. Handy to add to a script which is in your path so you can run it from any repository (a la 'svn_clean.sh').

Email yourself a short note
I created this so I could send myself an email alert when a long-running job was finished, e.g., $ my_long_job.exe ; quickemail my_long_job.exe has finished

parrallel execution of a command on remote hosts by ssh or rsh or ...
parrallel execution of a command on remote host by ssh or rsh or ... very useful for cluster management (software update)

Fetch every font from dafont.com to current folder
Requires aria2c but could just as easily wget or anything else. A great way to build up a nice font collection for Gimp without having to waste a lot of time. :-)

Open a manpage in the default (graphical) web browser
An easy alias for opening a manpage, nicely HTML formatted, in your set internet browser. If you get a "command exited with status 3" error you need to install groff.


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