The current high lumen output LEDs use multiple chips on a single die. The Seoul Semiconductor Z-Power LED P7 and the Cree XLamp® MC-E LED are two examples that are in popular use by flashlight modders.
I recently bought a DealExtreme Cree MC-E LED 3-Mode Drop-in Module ($18.30 USD) for my Surefire 6P flashlight (the 6P body is bored to work with a single 18650 battery).
The DealExtreme P60 size drop-in works with 2.7V~4.2V – a single Li-Ion 18650 battery, single RCR123A battery or CR123A battery. There is also a not too low level mode and annoying strobe mode. In the Surefire 6P host (about 5.2″ long – 13.2 cm), the DealExtreme Cree MC-E drop-in is an extremely bright flashlight in a small package. There is an extensive list of similar sized flashlights that use P60 size drop-ins in this Candlepowerforums.com thread.
DealExtreme seems optimistic in their description of the MC-E drop-in brightness as 410 lumens. It has more flood and less of a hot spot than the Malkoff M30. For comparison, my Malkoff Devices M30 output is rated at a realistic 235 lumens. My SSC P7 mod, inspired by jirik_cz, gives me the feeling that I am seeing everything. If not for the $125 USD cost, I would be all over the Malkoff M60 MC-E (NLA).
In my flickr set below, there are beamshots comparing the Cree MC-E, Cree XR-E and SSC P7. I centered the beam of each light on the scrawny tree against the fence.