Carmen Electra's Ultimate Workout Mix, Vol.
Music Presents: Randy Couture's Workout Mix, Vol.
According to the Nike+iPod Sync page on Apple's website, the iTunes Music Store will "soon" be stocking up on Continuous Workout Mixes:
Personally, I'm most interested in the Continuous Workout Mixes and the Sport iMixes.
A Tribute to Lady GaGa & Ke$ha Workout Mix (60 Minute Non-Stop Workout Mix (128 BPM))
Best Of 2010 Workout Mix (60 Minute Non-Stop Workout Mix (130 BPM))
Essential Workout Mix: Disco Remixed, Vol.
Essential Workout Mix: Non-Stop House, Vol.
G-Rated 90's Workout Mix (Aerobics, Cardio & Fitness Workout)
Essential Workout Mix: Dance Hits!