company that sells a recessed deck light kit which I find pretty interesting.
The kit is quite simple; the lights are LED, so they're low voltage. They sell a special drill bit which makes installation simple. Extra lamps can be purchased. Up to 20 lamps can be run on one transformer. Remote controls and dimmers are even available.
Best of all, I called the company, and their kit works on 220 volts as well as the 110V common in the USA.
I reconnoitered the deck when I was at the the house in December, and I think installation would be quite straightforward. On the other hand, we're not there very often during the dark months, so maybe such a setup is superfluous. Still, it's fun to think about.