I don't use my iPod in the Half but am thinking of getting that new clip-on Shuffle for the Full next year so thanks for bumping this up.
Since I don't currently use mine for the races and only training I have a mix of just those that I like but thought I'd share a couple of my fave energy boosters...
Reflections of Earth (Illuminations) I love the beginning and the faster pace sections. Pretty good when I'm on the ellipitical plus sometimes I listen to the beginning and when the beat slows I move to another song. Better for training for me than for a race but Susan has it on her mp3 and uses it during the half when she needs the boost. She listened to it as she entered Epcot in 2006 and was in heaven
I recently added Cup of Life by Ricky Martin
UNWRITEN!!!! it's my FAVE after all our books are unwritten and we're all reaching for something in the distance

It's by Natasha Bedingfield
Miracle Fingers by Off Kilter (Disney band)
Hawaiian Roller coaster - Lilo & Stitch
We Go On - though I won't use it in the race for fear I'd cry LOL (Illuminations) I tend to think of the group and the races as a whole when hearing this song.
This is how a heart breaks - Rob thomas
He Mele no Lilo - Lilo & Stitch
Run Run Away - Off Kilter
Welcome Medley - Epcot (seems to be a fave here with the group LOL)
These would be the songs that get the most use when I'm training.
Move Along by All America Rejects! Whenever I hear that driving to/from work I think of that being a good song! Thanks for posting that I needed the reminder to add it to my list and since I don't own Hercules or Mulan's soundtracks never thought of I'll make a Man out of your or Go the Distance! Those are great! THANKS!!!!