That makes me think, can there be something using which I can talk to my doors or for that matter to my car as a whole, lights, AC and gas supply at home to know their status? Can they tweet? Can they all be connected to small systems which can keep track of their status, receive tweets, understand the instructions, act on them and reply? Its quite possible. There are already automated systems or robots which can tweet; used for many reasons like 'to do reminders', 'dictionaries' etc. But mostly they are all just computer programs. What if the computer programs are connected to real things? Thats the idea.
Why Twitter? Well Twitter is not the only way this can be implemented. It can also be done using email, chat or SMS. Twitter coz there are multiple ways of tweeting and for all of them you need to know only one address. You can use SMS, your Twitter app on you phone, twitter.com, email, other twitter clients the options are many.
So next time when I'm half way through to work, and if I get doubts about if have locked the doors, I just tweet or DM
ooomz: @ooomzdoor status
ooomzdoor: @ooomz open
ooomz: @ooomzdoor Lock Sesame
ooomzdoor: @ooomz door locked
I can then sigh in relief and continue walking to work; may be praying that Twitter should be up all day :)