Never built a ROP but that is a classic hotwire mod. I did build a Mag85, which uses 9xAA NiMH cells to overdrive an 1185 bulb. It's ~1200 lumens, but runtime isn't so great LOL.

Was working around the house with the FIL last year and he grabbed the Mag85 to use it for something. He noted it was really bright. I was up in the attic and didn't see what he did with it, but a few minutes later I noticed a burning smell. We were running electrical wires for some ceiling fans, so I triple checked that wasn't the cause. I climbed down from the attic wondering WTF was happening. Turns out he had left the Mag85 switched on, placed head down on my desk, for several minutes. I could see the smoke coming out from under the light. It didn't start an actual fire, but probably would have if there was more fresh air available under the head. It did char the hell out of my desk. <img src="/forums/images/graemlins/lol.gif" alt="" /> Since that little incident I've kept that bad boy light segregated from the others so it won't cause any trouble. <img src="/forums/images/graemlins/evil.gif" alt="" />