Chris,
You didn't give any details of what you want, so I will throw a few out there for you.
If you don't mind the size of the Maglight (you did not say AA, 2C or 4D etc) I will default to a 2D to make it interesting. Everleds makes a voltage regulated drop-in for the 2D to 6D Mags that is focusable and puts out decent light. It uses a Luxeon 1.2 watt LED and costs around $40
You mentioned the X5 and X1 for spotlighting badguys... I would not recommend those as they are more of a flood light (the X1 is not available, but when it is...it is not very high output) Getting a small light to put out a spot beam is not very easy, with LEDs it makes it harder to achieve.
Probably the smallest light that is very blinding would be the Surefire L4. It uses a 5 watt Luxeon LED, is regulated and consumes 2 lithium 123A batteries every 65 minutes... order a dozen batteries with your order! The L4 costs around $140.
The modders on this forum make some utterly insane lights! The Mr-X comes to mind, a light that is regulated, pushes the LED to 10 watts and comes in the 2C Mag body. Three lithium 123A batteries are what that monster consumes.
Elektrolumens builds a 2D sized light that uses 6 AA or three lithium batteries, it runs the 5 watt Luxeon and his spot beam 30mm optics. It is brighter than the Surefire but not as bright as Mr-X.
Inretech builds lights that use three 1.2 watt luxeons or three 5 watt luxeons. He can build it up to take NiMH batteries which is a good idea at 15 watts of output! If you want more of a spot, swap out the stock NX-05 optics for Fraen low profile optics to nuke the retinas.
A really small light would be an Arc LS which runs 2 hours on one 123A lithium and is practically bomb-proof. They start at $65 and head up to $150 depending on what you want.
Surefire also makes a L1 that is about the same thing as the Arc, the difference is it can use one, two or three lithium 123A batteries. Costs around $100.
The last option is to build your own by visiting the Sandwich Shoppe and picking your parts. Wayne makes current or voltage regulators built with LEDs on them to drop into a Brinkmann Legend 2AA (prefered way) or minimag. Pick up the mineral glass option to replace the plastic lens for $1.50. If using a 2AA Minimag, get the Kroll tailswitch for a better on/off option ($4.50) The Q3L option for the Luxeon LED is a great idea in that it puts out more light than the stock one. It will run you $45 and is well worth it. I have two BB400 Q3L and they work well. You missed the Badboy 500 R2H offer, they are even brighter and are driven harder for more output.
If you go for the Badboy current regulator or Madmax+ voltage regulator (brighter initially than Badboy) hook up with Elektrolumens for some Fraen low profile optics ($5) They will focus the beam tighter and give a better throw than the stock NX05 optics.
Sniff around the CPF and learn about all the different lights mentioned above plus others such as McLux, Space Needles, Lambda Illuminators, Micro Illuminators, Nano Illuminators and Pico Illuminators. If you can dream up a light, the modders on this forum can build it...or have already done so!
Enjoy the CPF, keep an eye on your wallet and have a good time. /ubbthreads/images/graemlins/thumbsup.gif