I've written about the trap bar and use it for many different exercises.
For conditioning, load up light maybe 275-300#, then do a set of 5 lifts, hold and walk until you can't, set it down, regrip, set of 4, walk, set of 3 walk, set of 2, walk, 1, then fall over. Had people who favor the total nanny state whine about farmers walking a trap bar. Just figure it out.
Ryan Viera posted about doing explosive jumps while the trap bar is on blocks. I would place the bar on 8 inch high timbers and try and jump straight up. Very nice for throwers.
Like others who have posted, doing lots of trap bar lifts heavy seems to help both my squat and dead. Again, my throwing is more important than how much I total in a power lifting contest.