TrackIR
Well having seen some of the P3 videos and how awesome TrackIR makes the experience, I just ordered my own TrackIR w/ headset clip last night. It shipped this morning and should be here tomorrow.
I read a bunch of reviews on it first, because it is a bit pricey, however I couldn't find a single review that didn't absolutely gush about how incredible the equipment is. They all said it was a breeze to install, amazingly useful in air to air comat situations for keeping track of your opponents and that the immersion factor will simply blow you away.
I plan to get the most out of P3 when it ships because I just love WWI dogfighting sims. No radar, no electronic gunsights, no jet power. Just a prop, a gun and a lot of courage and skill needed to outfly your opponent. It looks like P3 AI opponents will have me challenged for some time too, judging by the videos.
Anyways, my rig is Duo Core 2 3.16ghz cpu, 2 GB DDR2 800 ram (corsaire extreme), 680i Nvidia motherboard chipset, 280 GTX 1GB video card and a 22" flat panel monitor. If my flying skills don't look good, at least the enemy aircraft shooting me out of the sky will.