Hi, I'm just reading through the Nerdkits guide again (eventually I'll understand everything)and I was thinking about the header.

From what I can see, the header just uses 2 inverters... and you can make an inverter from 2 mosfets (1 n-channel and 1 p-channel) - So, using just 4 components, can you make a quick n' dirty header to connect directly to the USB?

I would try it, but I only have n-channel and don't know what p-channel type to buy :)

Technically speaking, you're absolutely right... But keep this in mind... Chances are those 4 MOSFETs will cost you more than the buffer IC...

Actually here's another way to think of it... Take a look at any data sheet that gives the full circuit details... Actually even the nerdkits guide kinda explains it if I remember right... What I'm talking about is the fact that transistors (and MOSFETs) are at the core of pretty much every single IC out there... Even the mighty processor inside this PC I'm typing on is nothing but hundreds of millions of transistors all on a single wafer... Generally speaking as far as production goes, because the process is very similar, it really doesn't cost much more make the wafer for an MCU or a wafer for an IC or a wafer for a MOSFET... It's the engineering, tooling up, etc that cost... The point is... When it's all said and done, manufacturing a 14 pin IC generally costs the same as a single MOSFET... So even though it's only 4 mosfets it would end up costing more... ;)

If you want some really cool reading material, if you're not familar with it, look into how wafers a made... Look at an image of the wafer of a microprocessor... It's something akin to staring into the vast expanse of the universe... ;)