I purchased the Nike footpod, and also bought an aftermarket pouch on eBay, to hold the pod. I've been using this solution for 6 months now.

Similarly, I use this system in conjunction with my Polar 620i, which doesn't measure distance.

Overall, the system works very well. I found at first that the pod overestimated my running distance, by about 5% (which is significant). I tried to move the position of the aftermarket pouch so that it would be closer to the full, in-shoe Nike version. I quickly learned that position of the pod had NOTHING to do with accuracy. The pod is an accelerometer, and so don't waste your time with positioning changes. The pod pouch that I use keeps the pod snugly in place. Just lace up the pod pouch and go.

I do recommend that after taking an initial run, use the calibration feature on a 1/4 mile track. This really helps the Nike+ system to get very close to exact mileage. On a 10 mile run, I'm now regularly within .1 to .2 miles of accurate (which is close enough for what I want in training). Accuracy is good regardless of terrain or surface.

In addition to the mileage feature, the system gives you spoken reminders, such as saying "2 Miles to go", etc -- which is just tri geeky cool.

I find that I regularly look at my current pace on the display. To me, this alone is worth the price. While small on the display, it is still relatively easy to view. The only downside is that I now hold my nano in my hand instead of on an armband. I do this so that I can view time and pace data from Nike+ without changing my running position to look at the nano display on my arm.

$30 for the pod and about $10 for the pouch. For me, this was a good spend of $40. It does help to complement the Polar HRM without spending $250+ for a new model with distance/pace tracking.

Uploading the data to Nike+ is simple and easy, although Nike+ lacks the advanced data analysis tools that you find with Polar Precision. I upload data into Nike+ and then manually create a PPP entry to keep my training data loaded in one place.

The main benefit continues to be the simple integration with the nano. Music + training data equals goodness. Granted, the best solution may be to upgrade the Polar. However, the Nike+ is a great solution on a lower budget.

Overall, this is a highly recommended product solution that scores 4 out of 5 on my scale.

you bet solidad, only $30. For what it offers it's a great price. Looks to be exactly what your wife is looking for

In my experience it works less-well on a treadmill...not totally sure why that is. Another really cool feature is the nikeplus.com website, which tracks your data but also lets you challenge others (and yourself) with "virtual" races, distance goals, and more. All laid out in pretty useful charts and graphs. Really pretty cool.

A small group (from around the country) from my blog and I are using the system to train together - this weekend we're having an 11 mile race. Feel free to check it out at transition3.com, and feel welcome to join in if you like.

The Nike+iPod kit is a $30 add-on for the iPod Nano. It's a little receiver, which connects to the iPod, and then a little transmitter that you wear on your shoe (or in your shoe with special Nike brands.) The transmitter is an accelerometer, so it measures the movement of your foot and tracks pace, distance, and calories - sending that data to your iPod. With a push of the iPod's center button you can get real-time audio feedback on how fast and how far you're going, and then at home when you plug it into your computer, the iPod sends that data to a special nikeplus website to track your data.

Check out nikeplus.com. It's pretty cool.

That is very cool! I use it along side my 625X and it fun to compare the two.. For the case I really like the Marware Sportsuit Relay. It fits the plug in chip at the bottom of the nano and has a clear window to see and navigate the ipod. heres a link
http://www.marware.com/cgi-bin/WebObjects/Marware.woa/3/wa/selectedCategory?catalogCatID=238&wosid=7tUvjHiuEAki35uH43R3ZM

Thanks, I think I am going to have to look into that.