if you know how to manipulate the files for Kaplan you can get it into mp3 format and those are definitely helpful during third year. I went through most of those with my rotations.
also check into itunes for some of the podcasts, there are some medical ones from reputable sources that will review topics that can be very helpful during third year. another good site is The Medkast (google it), some guy reviews a chapter from a book and gives you the main points with a brief quiz at the end. he hasn't updated it in a while but the info that is there is helpful.
do a search on the forums here as some people have listed some great podcasts as well.
finally, you probably got a cd of heart sounds when you purchased your stethoscope, it might be helpful to convert to mp3 and listen to that while on medicine/cardio.
J