I'm making a water tower/sculpture. I need a controller board to:
- charge a 12V battery from a solar cell (and stop charging when "full")
- run a pump from the battery
- turn off the pump when the tank is full
- turn on a couple of valves to water plants
- possibly include basic solar tracking using servos
- A motor shield will probably be helpful
In good Intel fashion, I've created project plan and schedule 
I'll post those next time.