The official expression used for variable names, class names, etc. From http://www.php.net/manual/en/language.variables.basics.php

Valid IP Octets include: 1-9 & 11-223, then 0-255, twice, then 1-254 but with no leading zeroes. This will exclude the 10.0.0/8 private IP range, the reserved and multi-cast range, 224.0.0.0 and up, as well as the private IP ranges 172.16.0.0/12 and 192.168.0.0/16. In other words, this will addres...

a-123-2134

Get the body of a specific cookie from an HTTP header.

as title

Will extract URLs from text string if they have a space or line ending at the end and are not wrapped inside a string delimiter

Use this to find wich mods (in Minecraft, Forge) errored out in the Crashlog

Akamai Logs

This regex is a mashup that strips protocol, domain and URI into seperate capture groups.

Detects hiragana, katakana, kanji and japanese alphabet

/^1-9{3} ?(?!sa|sd|ss)[a-z]{2}$/i

Find a bunch of different types of email with this RegEx