Why do you need the Nike + shoes if you have the sensor?

Nike say that the Nike+ trainers (which are more expensive than other Nike trainers) are needed since they hold the sensor properly in the sole of the shoe and this prevents the sensor bouncing around and giving false readings - and so the Nike+ system is more accurate using the shoe.

They forget to mention in their advertising that the Nike+ shoes are more expensive than others in their range (and other brands shoes), they might not fit your feet as well as other brands or models and might not be the best for your running style when compared to other brands or models. They conveniently mention that you can couple the Nike+ to an Apple Ipod, but forget to mention that there are far cheaper MP3 players out there - lighter, smaller and as much capacity as the ipod that won't accept the Nike+, basically if you get the full system you are forced into buying overpriced equipment when there are better cheaper alternatives I think.

You can get a foot pod 'sock' that sits under your laces and holds the sensor for any foot pod system (other people such as Timex, Garmin and Polar make similar systems) as an alternative to the Nike+ trainers thought NIke claim this looses accuracy - which to be honest might by 5% to 10% different - but when you know how inaccurate it is you can adjust your runs to suit quite easily.

Having said all of that, I am not a fan of the Nike+ system - basically because it ties you to paying too much for your other kit, and the only benefit I can see is the 'power tunes' function that plays a certain song of your choice at a certain point in your run to give you a boost. Without this you can just skip forward a few tracks on any MP3 player to get your 'power tune' manually without spending £80 on an ipod when a £20 MP3 player is just as good for running

The Nike+iPod does not require the Nike+ shoes. Good thing too, because they're generally not as good as some of the other Nike shoes. All that is required is that the sensor be attached to your shoe in some fashion.

A popular method of keeping your sensor on your shoe is the Shoe Pouch. It works, it's accurate, and it stays on. In fact, the same can be said about just about every similar product on the market. As long as the sensor stays on your foot, you will get remarkably accurate readings.

The Nike+ shoes have a space in the left sole (underneath the sockliner / insole) for the sensor. That's it.

No, you cannot put the sensor "in" any shoe otherwise. You can put the sensor in a pouch attached to the laces of other shoes and it will still work, however.

I actually have the Nike + shoes, not for nikes sensor and stuff but because they are the most comfortable shoes I have ever owned! They are so good! But Im not sure Im sure you could put it in any shoe :)