I'm experimenting with a teensy-weensy, tiny IC that works as a buck controller for driving high current leds. The chip is the LM3409HV. It can control LED loads up to 75 VDC and 5000 ma of current, so you can see the potential for such an led driver designed around this chip. I recently designed and had a PCB produced for this chip. I still have to adjust some of the component values as the first one tested produced 2700ma with a 27 volt input ( My target was 2000ma). Here's a photo of the first driver. Notice how tiny that little IC is. Its dwarfed by nearly every other component on the board! Let me know what ya'll think.