I'll admit to a playing "My Love" and Sexyback from Justin. I also like the timelessly cheesy one more time
Others on my playlist:
-Holding out for a Hero
-O Fortuna from Carmina Burana
-Dirty Laundry and Muddy Water from Seventh House
-Explosive by Bond
-Escape from Hellview by CKY
-Geek in the Pink by Weezer
-Little Drop of Poison
-Mi Morena by *sigh* Josh Groban
-Canto Allo Vita
-Remember Me
-Never Let Go
-Transylvania Concubine by Rasputina
-Ride of the Valkyries by Wagner
-You're Easy to Dance with by Danny Kaye
-Maneater by Nelly Furtado
-Dragostea Din Te by O-Zone
-Down by Gravity Kills
-Copa Cabana
As for inspirational, I can't pick one song, altho lately I do love Josh's new "Don't give up (you are loved)" Its an amazing song, and it always gives me a lift. Otherwise, most of my moving pieces are classical ones. I love Carmina Burana, and it always gets me moving.

Music is the way to keep motivated. I always tell myself to get through just ...one...more...song when i really want to stop.