Today only, if you own an IPhone, you can download the pro-version of Runtastic for free (.99 for Android).
I know most people either use RunKeeper or MapMyRun, but I read about Runtastic in the NY Times. Like RK and MMR, Runtastic also maps your route, pace, and time, but it has a more social component if you choose to use it. You can allow yourself to be seen by other users while exercising and they can send you cheers. Positive reinforcement in real time. Women may not feel comfortable with this, but you can easily choose to opt out of this feature.
A feature that I consider to be a huge plus is that you can set up an interval workout. Also the music is integrated into the app, so you don’t need to leave it in order to adjust your music.
I haven’t had a chance to fully play with Runtastic yet, but it looks good. And since it’s free (for IPhones), you might as well download it yourself and see what you think.