[Achromatic]

This may be a silly question, but some Googling didn't help - I don't have a Media Center PC, but am wondering if I bought a USB IrDA adapter, would that suffice for the IR side of things, or is it a completely different beast?

My goal from there would be to get things working with my Logitech Harmony (but I'm sure I can find that info later, I'm just wondering whether I am even on the right track...)

[Gamester17]

Best is to buy the official Microsoft MCE Remote and use its reciever, read:
http://forum.xbmc.org/showthread.php?tid=38585

I believe you need WinLIRC support for IrDA, see:
http://forum.xbmc.org/showthread.php?tid=36864
and:
http://trac.xbmc.org/ticket/4851

[gstreet]

i built my own ir reciever and use it with my logitech harmony 525, works flawless. u need winlirc and girder 3.