Ahh, the good old days when I didn't know how stupid I was.

Take a dozen Vicks inhalers.

Note the primary ingrediant: L-Desoxyephedrine

Your body can't tell the difference between it and meth.
If you look in the PDR for Abbot diet pills called
Desoxyn, you will see the primary ingrediant is methamphetamine,
formerly know as Desoxyephedrine.

Here's the typical Google search:
[link|http://www.google.com/search?q=Desoxyephedrine+vicks+lye&btnG=Google+Search&hl=en&lr=&ie=ISO-8859-1&safe=off&c2coff=1|http://www.google.co...safe=off&c2coff=1]

From memory, now:

Take the cotton out of them and soak them in a mixture
of water and 2% hydrochloric acid. Can't get it? Sure you
can, brick cleaner / aka muriatic acid, from the hardware
store.

Rip part the cotton filters.

Funnel through coffee filters to get rid
of the cotton and the menthol aromatic oil.

The next steps I'm real fuzzy on.

I seem to recall you need to pull out the Desoxyephedrine
by mixing with ether, draining off the water (hmm, from
the bottom?), then mixing with Sodium Hydroxide and a
bit more hydrochloric acid to bind the freebase Desoxyephedrine
to the hydrochloric acid, which them made Desoxyephedrine Hydrochloride,
also called Methamphetamine Hydrochloric depending on what
book you were reading.

You then needed to boil off the ether leaving the purple grey
crystals.

For those who don't know how to get the other chemicals mentioned:
Sodium Hydrochloric = Lye, aka drain cleaner
Ether = Starting fluid used to dry old carburators. Make
sure you get plain, no petroleum distillates added.

And yes, IT WORKED!!!!! Produced about a gram of pure
meth, 10 grams after cutting it to something that wouldn't
kill me when I snorted a line. For 20 dollars of Vicks
inhalers and random chemicals. I had people offer me $500
per gram before cutting.

I bought a mouse to try it out on before using it myself.

Damn thing ate it's way out of the box it was in and lived
in my closet for a month. I finally caught it when it tried
to drink from my used bong and fell in.

Part of the process was adding the lye and shaking / releasing the
ether until it would not react any more. The released a huge
amount of highly explosive ether gas in my living room. While
I was taking bong hits using the other hand. I should have
blown up.

One time I made it but screwed up the hydrochloric bind. You
count not snort it or eat it since your body needed the HCl to
absorb it. Didn't matter, though: I invented Ice, aka, smokable meth.

(Edit)

Further web reading shows that either the core ingredients were different
25 years ago or I was producing pure Ephedrine, not Meth.