Android secret codes

Android is now rocking in the mobiles world. All major cell phone companies are launching android cellphones.If you are an android user, i have some secret codes of android which will help you. Some of the android secret codes below:
Cell Battery, WiFi Usage etc Info *#*#4636#*#*
Restore Factory Settings *#*#7780#*#*
Format Phone *2767*3855#
Launch service mode *#*#197328640#*#*
Test WiFi *#*