That is so true buffdaddy!!!!
The best "bang for your buck" according to that chart shows that you get a measley 5.9 HP @ $129 for the pulley which comes to $21.86 per/HP.
Nitrous now, that's a whole 'nother story. An average nitrous kit comes to ~$500 (although you can get some for $350-$400). You can get up to 75 HP (on a v-4 at least). Plug it into the equation ($500/75HP) = $6.66/HP!!!!
That absolutely KILLS all other mods!
BTW: it's too bad that nobodies ever done, nor will do, that with the Cougar.