Since nobody ever mentioned these cheats, I guess nobody knows em' so I'll tell you guys about them.
The first one is how to put your GameBoyAdvance in deep sleep during the middle of the game! To do this just Press SELECT and the R button at the Exact same time during gameplay. If it works, then it should look as if the GBA was turned off.(You can tell if it's off or on because if the Light is on then your okay.) If you want to get out of sleep mode, press SELECT and L at the EXACT same time!(When in sleep mode the game doesn't Reset.)
Added by: patrickref May 16th 2005, ID#5059