I am doing this to some of places. It can get expensive depending on how you want to do it.
I recently purchased the August Gen 2 lock. It got great and shitty reviews depending on what site you go to, but I figured I'd give a shot. I will let anyone interested do their own research but I personally love it. Have had zero issues and it's pretty cool to see who comes and goes. The one downside I've seen so far....is I gave my girlfriend a "key" so obviously to use she has to download the app. Her access is pretty open because well, I'm dumb and trust girlfriends, so now when I leave the house the app notifies her that the door has been locked/unlocked. My midnight strip club ventures are now known!
There are wifi fridges and ovens and all sorts of shit. Been contemplating them but still on the fence. I do personally like the coffee pot. I found I never used the generic brewmasters with timer, because my schedule is never 100%. However I do find myself waking up in bed, grabbing my ipad, which I would typically do anyway to check on one of those lame games I play or read the news or see how many work e-mails I got blasted with the night before(IE do I need to wake up ASAP and get to my computer or can i linger?). So now I open the coffee app and start it up. Is it a gimmick, yes. Do I like it, yes.
My next move, but sadly it's still insanely expensive to do the entire house, is the smart lighting. Essentially each lightbulb has a little wifi signal. All talks to the main program and you can control the lights via a computer/iphone/ipad. Now that alone is neat, but still kinda lame. I mean...what's the difference between an app and a switch on the wall? In fact the app is more annoying. However where it starts to shine is the whole IFTT thing. So you link it to the August lock or NEST thermostats or some random motion sensors around the house and with a little time and effort you can write yourself a little program. If Im not home turn off all the lights but X. If motion sensor goes off turn on lights for 15 minutes. At 2200 dim the hallway lights to 30% and turn off all others....you get the idea. It's pretty badass. I was too lazy to do a before and after on my electric bill so not sure of the effect, but they are all LED and in theory with a smart program you'd use less lighting. All of the lights can do any color(16 million, like a computer) and all can dim. You can also save a lighting set. So I can save "movie mode" which dims all the lights in the living room to 25% soft green. Or "Sex time" and the main bedroom lights go soft pink!
The company I used was Phillips Hue:
http://www2.meethue.com/en-us/ but I'm sure there are competitors and such. As I said, expensive for an entire house but there is no reason you could not just do 1 room at a time.