Cisco - Regular Expressions

I have used regular expressions for years when configuring Cisco routers. However, the bulk of my use of them has been when configuring BGP. However now that I am using them for dial-peers in our Cisco routers used for our VOIP system, I have decided that I need to commit this information to memory. Up until now every time I write an regular expression I have to refer to the documentation.

For those of you in the same position as I am I have included some links.

Cisco.com - Dial Peer Enhancements - 12.1T
Cisco.com - Regular Expressions - 12.2
Brcraju Blog - Learn how to write a Regular Expression