A guy named Peter has set up a robotic watering system that can to take directions from an iPhone. When Safari's screen state goes from horizontal to vertical, it sends a status update to a web server via JavaScript that sets the watering can up or down. Although its rather nifty feature I feel that this technology is a bit too much to water your plants.

However use the same for turning your lights off is another thing altogether add a Bluetooth interface rather than the web link and you have a surefire winner.

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