Apple's new iPod nano has gone on a diet, returning to its long and lean look. Rock your workouts with the fourth-generation nano -- it's not just slimmer, cool new features have techies buzzing:

• A skinnier nano is possible thanks to an accelerometer tilt sensor which allows you to turn it on its side and the player shifts the 320 x 240 screen -- great for video. Flip it either way and the sensor adjusts the picture.
• The accelerometer also powers a shake-to-shuffle feature. Give a firm shake to get rid of that downer song during the height of your workout. Don't fret, running, biking and walking won't inadvertently shuffle away your favorite song, says one tech reviewer. Dropping it will.
  
• The new Genius feature can generate a 25-similar-song playlist from a single song. Sometimes there's an odd Apple in the Genius mix, but you can count on widening your playlist horizons. Flip through your album art with Cover Flow.
  

Now for the feature that really matters -- Apple doubled the nano's storage and kept pricing constant. The 8 gb model is $149, the 16 gb is $199. Or look at it this way, about the cost of two or two-and-a-half tanks of rockin' gas.