The Audio Osmosis CD's are great. I had them for about two months while studying for the MCAT. They are pretty expensive, though. My wife and I had our first child and I had to sell them to pay for formula (no lie!). They were great to use while commuting to work every day or traveling. The only negative is that they can be kind of corny with their jokes and sound bites. I would advise shopping around for them. I found them at books-a-million's website for $60 less than amazon. Hope this helps.