Go buy a 2C and build a 3x123 with a KPR112 bulb. It's a nice sized light, puts out a good amount of bright with plenty of throw, and has a reasonable runtime.
It's easy enough that anyone can build it, but requires enough effort that you'll feel like you've actually done something. It's also relatively cheap, and bright enough to give you a taste for hotwires.
You'll find plenty of well detailed instructions if you do a little searching, but the recipe is straight forward enough. First, get yourself three lithium CR123A cells. Do yourself a favor and buy them online for $1 ~ $1.50 each, instead of paying retail. Take one to the hardware store and find a piece of PVC where the cell fits nicely inside. Cut yourself a length of the PVC to hold three cells. Wrap a dozen turns or so of electrical tape around each end of the PVC to build it up thick enough so it fits nicely inside the Mag 2C. Replace the stock bulb with a KPR112 (cheap at Radio Shack). A Mag 6 cell Xenon (Numstar) bulb works pretty good too, but the KPR112 is a little brighter and a lot cheaper. For the finishing touch, you can get the heavy side cutters and snip a couple turns off the tailcap's spring. It'll work without cutting the spring, but it's a lot easier to get the cap back on if you do cut it.
That's it. Load in three cells and hit the button. You're probably looking at well over a hundred lumens. It should run for a good 60 to 80 minutes. The KPR112 probably won't last more than a couple battery changes, but it's cheap enough, so who cares? The Numstar would last quite a bit longer; that's what I have in mine. The 2C has a pretty good sized reflector, so you can dial in a reasonably tight spot for good throw. Have fun!
If you don't want to buy a new Mag host, you might be able to do the same thing in your 2D. Plan to use more tape on the ends of the PVC, and check to make sure the tailcap spring is going to be long enough.