One thing everyone failed to take into account is that the 200 watt bulb sends light in all directions, including where it is not needed. I'd say easily 50% of the light is wasted, if not more. A 200 watt bulb gives 3800 lumens. Since LEDs are more directional (even Luxeons with no optics send all their light over less than a hemisphere), you can get by with probably 2000 lumens or less for starters. Now add in the fact that the bluer light from LEDs is about 60% more effective for seeing than an incandescent and you're down to 1200 or so lumens. You may even be able to get by with less, but 1200 lumens puts you at maybe 18 LIIIs consuming 2.4W (@700mA) each, or about 43 watts total. Sure, this will be very expensive (~$200 for the Luxeons alone), but the heat can be dealt with by using a 5"x10" heat sink available in online surplus stores for maybe $10 to $15. The Luxeons can be mounted directly on the heat sink. The whole thing will probably get no hotter than maybe 50°C.
Depending upon how much you use the worklight, this may be a viable solution. If nothing else, the LEDs will last many, many years even being used 60 hours a week.