What effect does tasker/locale have on battery life? Locale and tasker look pretty cool. How much effect will they have on battery life?
I am the developer of Locale.

Battery life is a key metric that we test extensively.  The only feature in Locale that has any real effect on the battery is the Location condition.  At the time of this writing, the Location condition in Locale 1.4.3 can accurately detect 100-meter location changes within 4 minutes on average, while using 3% or less of the battery.

If you've configured Locale to turn Wi-Fi or Bluetooth on/off, then battery life may actually improve depending on the exact configuration.