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Remove color codes (special characters) with sed

Always tail/edit/grep the latest file in a directory of timestamped files
zsh only If you have this command in your history, you can always re-run it and have it reference the latest file. The glob matches all timestamped files and then the resulting array is sorted by modification time (m) and then the first element in the sorted array is chosen (the latest)

Generate an XKCD #936 style 4 word password
4 random words are better than one obfuscated word http://xkcd.com/936/

Block all IP addresses and domains that have attempted brute force SSH login to computer
Searches all log files (including archived bzip2 files) for invalid user and PAM authentication errors, both of which are indicative of brute force attempts at logging into computer. A list of all unique IP addresses and domain names is appended to hosts.deny. The command (and grep error messages) will work on Mac OS X 10.6, small adjustments may be needed for other OSs.

Synchronise a file from a remote server
You will be prompted for a password unless you have your public keys set-up.

list ips with high number of connections

Create a backup copy of a MySQL database on the same host
This should probably only be used for testing in a dev environment as it's not terribly efficient, but if you're doing something that might trash a DB and you still want the old data available, this works like a charm.

Display a list of all PHP classes that are called statically
Searches all .php files for a static instantiation of a class and displays the class names along with their frequencies.

For a $FILE, extracts the path, filename, filename without extension and extension.
Useful for use in other scripts for renaming, testing for extensions, etc.

Share a file quickly using a python web server
Raise your hand if you haven't used this at least once to share a directory quickly


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