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count the number of specific characters in a file or text stream
In this example, the command will recursively find files (-type f) under /some/path, where the path ends in .mp3, case insensitive (-iregex). It will then output a single line of output (-print0), with results terminated by a the null character (octal 000). Suitable for piping to xargs -0. This type of output avoids issues with garbage in paths, like unclosed quotes. The tr command then strips away everything but the null chars, finally piping to wc -c, to get a character count. I have found this very useful, to verify one is getting the right number of before you actually process the results through xargs or similar. Yes, one can issue the find without the -print0 and use wc -l, however if you want to be 1000% sure your find command is giving you the expected number of results, this is a simple way to check. The approach can be made in to a function and then included in .bashrc or similar. e.g. $ count_chars() { tr -d -c "$1" | wc -c; } In this form it provides a versatile character counter of text streams :)

Google text-to-speech in mp3 format
same but redirecting to player and putting whaever text line.. works on my ubuntu machine ...

Rename .JPG to .jpg recursively
This command is useful for renaming a clipart, pic gallery or your photo collection. It will only change the big caps to small ones (on the extension).

A bit of privacy in .bash_history
Don't track in history commands starting with whitespace. Moreover ignore duplicates from history. To be set in .bashrc ex. $ export HISTCONTROL=ignoreboth $   echo antani $   history|grep -c antani 0

Generates a TV noise alike output in the terminal
Generates a TV noise alike output in the terminal. Can be combined with https://www.commandlinefu.com/commands/view/9728/make-some-powerful-pink-noise

Scale,Rotate, brightness, contrast,...with Image Magick
$rotate: the rotate angle $width, $height: width and height to scale to $birghtness: change brighness

Create an alias, store it in ~/.bash_aliases and source your new alias into the ~/.bashrc
This is useful if you use a shell with a lot of other users. You will be able to run "topu" to see your running processes instead of the complete 'top -u username'. Read more on alias: http://man.cx/alias

Extract domain from URl
Extracts 2nd-level domain part (or 3rd level, for co.* or com.*) from the URI's hostname. See sample output.

Find all file extension in current dir.

Console clock
Shows a simple clock in the console -t param removes the watch header Ctrl-c to exit


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