Literally - the heating is just always on when it is on.
Fixing this with a thermostat in the hall is also a bit pointless - at least get one that can be moved elsewhere in the house, and that can be turned on and off over the Internet. Otherwise seems a bit pathetic in 2013.
@adebradley recommends http://www.heatmiser.co.uk/web/index.php
@handelaar has found this http://x10modules.com/shop/product_info.php?products_id=100 which looks promising
I just bought a nest 2. It's awesome. Just know that the glass on the front is supposed to have a stylish "crack". I thought mine was broken and returned it before realizing the new one had a "crack" in the exact same spot.
Nest looks ace - however, I'm not sure it works well with UK boiler/radiator based heating systems.
Also, doesn't look like it helps me add separate control of different rooms to the system.
I've been wondering about LightwaveRF (http://recombu.com/digital/news/lightwaverf-home-automation_M11004.html). Does the X10 stuff provide boiler interlock, or does it just turn on and off individual radiators? Currently our thermostat is in a room which has an open fire, a log burner, and two radiators with thermostatic valves...
I've been looking at this for a while and have come up with a few options I'll share here:
I haven't even considered X10 as I have powerline adapters in my house and I hear they don't play nice together
I've been impressed with Radio Thermostat's wifi-enabled thermostats & cloud/mobile service. I've got the 3M-branded 3M50 (their CT30) which goes for about $100 in the US. iPhone/Android/web remote control would get you control away from the thermostat. I don't know what a real multi-zone system looks like, but the web/mobile UI can control and schedule multiple thermostats individually. The company's published docs for the control/inquiry REST API exposed on the devices themselves, too, which is nice.
Also see the recent Almond+ kickstarter. $100 USD for an 802.11ac router with a small touchscreen and Zigbee + Z-Wave wireless device control for things like thermostats and lighting. It apparently extends those device controls to phones & tablets over the internet, too. Projected delivery in late summer.
Just happened to pop by, and I can certainly recommend the Heatmiser wifi thermostats as well. Controlling your heating with your smartphone is rather good, and they have a published protocol if you want to hack your own.
Added bathtub plug, rack for keys, kitchen faucet aerator, silverware…
… stacker, and carpet corner support
In the end, I took easy / lazy route to this and got a Hive (by British Gas) while upgrading my boiler anyway (#1). It had good reviews (http://www.pcadvisor.co.uk/reviews/digital-home/3524456/hive-active-heating-review/) and is British, and doesn't involve more control of my life by Google.
So far, seems good - nicely made interface on Android, iOS and Web. And works and is useful to be able to control heating remotely.
I'm not convinced it is logging my temperature in detail permanently - you can only get lots of datapoints today yesterday in the graph interface, or average each day for longer periods. Average across whole day is useless!
Overall, I don't think this kind of thing is a life changer, but it is useful.