I just ordered this from dx.com:
I was tired of the dim light, the standard W5W bulb gave, so I got this - It's REALLY BRIGHT! Fit's perfectly in the W5W socket and holds itself in place.
I'm a little unsure which Ford models that does not have this type of roof light, but this should at least fit any Fiesta, Mondeo and Focus that does not come with maplights. Be sure to verify that it's a W5W socket - If it's not, I have seen other variations of similar LED boards on ebay with different socket types.