I'm looking for a reminder / task app that will remind me to do something BEFORE I leave the house Etc
Tasker, Llama, and AutomateIT are a few apps that have events or actions that can be triggered. I think they all have varying capabilities when it comes to location based triggers.
If you use Bluetooth, then if one is in your car and when turned to On, that could be another method to trigger a calendar or reminder app.