Here are some tips that you may or may not know about your phone.
You can check an md5sum from Astro File Manager by long pressing the file then hitting details.
Holding down the Home button shows you the last 6 programs you used.
When your phone is laying flat and a call comes in, you can flip the phone over on it’s face, and it will ignore the call.
Hold down the power button, to see a list of power & network options
Hold down the search button to bring up the voice command menu
Press home twice, or pinch the screen to see all screens
Click Settings->About Phone->Battery to see detailed stats of what is using your battery
Bump Charging: To get the most out of your battery, charge till light turns green, unplug, power off, plug back in. You’ll see the light go amber again indicating it’s charging some more. It should charge for several more minutes.
Not android specific, but seems to be needed a lot… Dial *228 option 1 to reprogram your cell towers. Try this first if having problems with 3g
An interesting list of codes can be found here. Use some common sense before attempting any of these.