We have one of these

http://www.lumie.com/shop/products/dawn-simulators/Bodyclock-SUNRAY-100

It is, pardon the pun, brilliant. Mr Ding has to get up for work at 5.30 so on all but midsummer mornings it beats the real sunrise. Much, much better than some noisy thing blaring out.

The other thing it is useful for is as a dim light to help him see his way around the room if he comes to bed after I'm asleep.

Well worth the expense I would say