This is one of those times when Stoichiometry and Thermodynamics pays off in a household setting. Trust me, I'm not a whacko and this stuff really works.
The one thing that tends to kick people's butts with butane lighters is that they work great until you have to refill them. Then, a perfectly good lighter tends to get thrown away or that refill only lasts for 1/10th as long as when it was new and people get frustrated.
The secret to getting a good refill is what I call "Delta T". Basically, with all things being equal, you need to maximize one of the properties of gas flow (in this case, Butane which has some goofy properties). Without being in a lab environment, this can be the frustrating part.
Without all the science mumbo-jumbo, here's how to refill a lighter to like-new or better levels:
Start with a good can of Butane gas. Avoid the cheap stuff. Cans of Butane usually come in 2.5 to 10 oz. (80 to 290 ml) sizes. The main danger with Butane is that it sheds thermal energy like the plague when it goes from a high pressure environment (in the can) to a low pressure environment (regular air pressure). What all of that means is that if you can see liquid Butane outside of a container,
AVOID GETTING IT ON YOUR SKIN. In normal air pressure, liquid Butane will be super cold (like -50 degrees), cold enough to "burn" you.
You'll also need to purge your lighter before you can refill it. This doesn't make sense at first, but you want the pressure in your lighter's "tank" to be the same as normal air pressure. You can find tools to purge a lighter online, or find some thin metal tubing (check the tip of your Butane refill can to get an idea of what kind of tubing you'll need). Carefully purge your lighter, make sure any Butane doesn't touch you.
Now comes the "Delta T" part. People tend to figure out that the higher the pressure in the refill can, the better the refill. This is only half right. What we're going to do is use different
temperatures to maximize the refill.
So, instead of heating the can of Butane (dangerous), chuck your purged lighter in your freezer for 1 to 2 hours. 
Believe me, this works so well that you'll wind up with more fuel than you would get in a new lighter. Once your lighter is really cold, grab your can of Butane and hold onto it for a couple of minutes. This will transfer a little body heat into the can, not much but you don't need much with Butane.
Now, pull your lighter out of the freezer, make sure its upside down with the refill port on top, and start the fill from the refill can. I usually do a "ten count" at first, then pop the refill can off for a couple of seconds, then pop it back on for another "ten count" before I call it good.
Now all you have to do is let your lighter warm back up to room temperature. Its a good idea at this point to adjust the flame setting to its lowest value.
Even with the adjustment at its lowest setting, your lighter is going to HISS a bit for the first 3-5 lights.
If you're skeptical, that's cool. Let me prove it to you.
As a bonus, I can bet you a dollar to a donut that Chazlie can't help but smile when he reads this.
If your an egg head who enjoys a good math problem, we're exploiting the equation
PV=
nRT
by keeping the values of V ,
n, and R constant so we can manipulate the values of P (pressure) and T (temperature).
See? That Thermodynamics class finally paid off!