Non-Arduino Solar Charger

Do you think there is a great alternative to the current solar charger?

Today, there are many DIY Solar Chargers that are alternatives to the current commercial products. Do you think there is a better design for a solar charger that is not run by an arduino?

What charging system are you looking at that is using an Arduino?
I would assume the arduino controls panel tilt etc. Maybe even detect charge level and react accordingly.
Why on earth would you use an Arduino ?