well, there are more than a few candidates, but you really need to describe in more detail what you want from the light, and what size you consider "pocket-sized" as it differs for everyone.
There are a whole lot of lights with screaming bright output you can consider, off the top of my head, there's the Mr. Bulk Chameleon, DSpeck FireFlyIII, Orb Raw, Orb Raw NS, Jil Intelli, Peak Rainer (CPF Special), Amilite NeoT3. All these in the list require rechargeable li-on batteries to run at optimal performance, except for the Amilite, which need to run on non-rechargeable batteries. They all also have their pros and cons, but it's probably best for you to read up firsthand on these, instead of me boring you with my impressions =)