Here are more Android Tips for this site: http://android-tips.com
I did want to copy paste more tips, but am not sure what the rules are regarding that in this forum.
Reduce brightness of the screen in settings.
Limit internet connection to use only 2G networks.
Use wifi, bluetooth, gps only when needed.
Setup shortcuts to the setting enable page using anycut to do it easily.
Keep your droid clean and organized:
Long press on the dashboard to add widgets, icons and folders.
Long press on icons and drag them to the trash can that appears.
Long press on icon and drag it to the next screen. You might need to hold the icon at the edge for a sec to go to the next screen.
Long live the long press!