I just love books! Especially a GOOD book! I have found that on days I just don't feel like doing 30 minutes, I can grab a book and pass that time in what feels like 5 minutes. The workout may not be as intense as it is when I am not reading, but reading gets the job done. I have found that when I am at a part of the book I can't wait to find time to read, I will hop on the elliptical just to give me a reason to stop my regular routine, and read without guilt!!
Sometimes when it's time for working out, you just don't feel like doing it. For those days, if you have something else to focus your attention on; a TV show, a movie, a book, a book on CD, or whatever you can do while working out, you can kill two birds with one stone. Get lost in a good story, and those minutes will fly by.