I'm building the whole suit.  I've been planning halo-ween for a while now.  
In progress:
helmet, of course.  You've seen the status of that project.
Shoulders - Those will be next, seeing as they are symmetrical on both sides and are fairly easy to sculpt.  I'm about 1/2 done with the clay sculpt on this.
Chest piece is probably going to be last.  It's going to take the most amount of clay.
The feet are 1/2 done clay sculpts.  I'm not really sure what direction I'm going to go with those.  It's still in the experimental stages at the moment.
All in all, I have several pieces going at one time.  They should all be done and ready to rock by october 
