For the people wondering what they get for having played halo 1 on pc or mac this is what you get for entering your cd-key for either one for halo 1 pc.
 

i just dug up my dust covered Halo PC case to get the key. =D yay more baubles!

Wish I had a key :(

" i just dug up my dust covered Halo PC case to get the key. =D yay more baubles! "

" @jadeskye said:

" i just dug up my dust covered Halo PC case to get the key. =D yay more baubles! "

If you played online before May 26th, 2010 you're ok, but it won't do you any good to register a copy of Halo PC anymore :( 
http://www.bungie.net/Forums/posts.aspx?postID=46755796&postRepeater1-p=1#46763336 "

No way to input a Halo 2 PC code eh? Oh well.

What if you have had the game for years but never played it online?

Damn, I sold that shit years ago.

That is actually bad ass. Now to get my 360 out of the closet and sent out for repairs for the 10 millionth time.

" No way to input a Halo 2 PC code eh? Oh well. "

So do we enter the CD-key in the game itself, or is there some web interface that I have to go through? 
 
Edit: Nevermind. Turns out you input the key on your account on Bungie.net.  
 
Weird is that I apparently have access to the Halo 2 nameplate, even though I don't remember every playing Halo 2 online. But I don't have the Halo nameplate for having Halo PC, 2, and 3, though.

I'm assuming the "halo" name plate is only for Halo 1 PC not Halo Original Xbox or Halo 2 Xbox right? Kinda stinks I can't get it even though I own a clear green Halo xbox but still a nice lil nod to the more loyal fans. :D

I'd almost forgotten about the bonus for Combat Evolved owners. It looks like a very nice little extra.