Many kids have those step activated lights on their shoes. I believe they started as a novelty in adult shoes about ten years ago. I assume there's a small microswitch that closes each time the foot steps down, which activates a .5 second light. And I'm pretty sure this system is removable from the shoe.
if you took that same technology, but instead of the switch activating a light, a small radio pulse would be transmitted. So normal walking would produce a low frequency pulse wave. Running would raise that frequency.
Many platforms could receive this pulse for various uses. For example, a wrist watch type device could use this data to calculate how many steps you take in a day. It could measure distance for running, etc. With a built in digital compass, it could give specific directions for walkers
Perhaps a device that notices an increase in pulse frequency, and then measures the amount of time between pulses, and applies that data to a parameter (in the same fashion key contacts work for velocity controlled keyboards- a smaller amount of time between the 2 switches closing on one key = louder volume for that note).
Maybe that data could control the fan speed on one of those "personal cooling devices". A slow walk would keep the fan normal, but when you start to run, the fan speed increases.
Pulse data for your daily life!