Re: What would be really nice...
Something happened yesterday which started me thinking on these lines. The doorbell was rung by some dodgy looking character asking for scrap. Ideally I'd have got the camera out and got a photo of his van just in case but didn't get chance.
What would be an automated alternative? There's already a porch light controlled by a separate PIR detector. That provides a power source from mains and maybe, with a bit of surgery and an opto-isolator, a trigger signal. Combine that with a Pi, a camera and wifi - and the current Pi B already has wifi - I'd have a camera that could be paired with another Pi indoors recording onto an SD card snippets of anyone approaching the door. That would be so inconspicuous it's very unlikely to be taken in a burglary. No dependency on an external IoT service. In fact, if one of the Pis were set up as an access point they could have their own SSID and not need to be connected to my home network at all.