Android: Secret Codes

I was learning about the up time v.s. awake time of my android phone, and I came across a hidden code which shows some interesting information:

*#*#4636#*#*
My phone shows a testing menu with the following options:
* Phone information
* Battery information
* Usage statistics
* Wifi information

Sadly, the battery history option I'm looking for is missing :(

A complete list of secret codes

Bonus:
Not specific to android, should work on regular phone:
*#06#
shows the IMEI (International Mobile Equipment Identity)

Ref:
App for checking whats keeping phone awake on Gingerbread - Android Forums