How to rebuild a digital clock into a Lego case.
I did this because the current kitchen clock needs a new battery & as a consequence, is always showing cowboy-time. I needed a new one, that plugs into the wall.

Step 1: Take the Old Clock Apart

You need a digital clock, a screwdriver, a sharp knife, and to state the obvious, Lego.

Remove all the screws & pull it apart, taking care that none of the internals are damaged as you do this.

See pictures for details on the internals.

Seems I got one of these:
http://www.argos.co.uk/webapp/wcs/stores/servlet/Search?go.x=4&jspStoreDir=argos&catalogId=651&referredURL=http%3A%2F%2Fwww.argos.co.uk%2Fwebapp%2Fwcs%2Fstores%2Fservlet%2FSearch%3FstoreId%3D10001&langId=-1&searchTerms=255%2F0431&referrer=COJUN&storeId=10001&go.y=11

Step 2: Rebuild With Lego

The exact design depends upon the bits you have, this sequence of photos shows the build around these guts.

Step 3: Switch On

In order to use the buttons for setting the time, I had to lift the hatches and press with a Lego stick.

The display looks better in poor light because I've removed the green filters. However, I could chop the outer filter add it back, if this is too difficult to read too often.