Hmmmm... here's some 24V cordless drill packs... expensive but sort of simplifies things. There are also some ready-made lights that use those packs. I wonder if it's feasible to convert the lights to use that Osram bulb.
http://www.all-cordless.com/ma24v3nimasl.html
http://www.amazon.com/exec/obidos/tg/detail/-/B0000523XJ/qid=1092293133
http://www.all-cordless.com/ma24v3nimasl.html
http://www.amazon.com/exec/obidos/tg/detail/-/B0000523XJ/qid=1092293133