This is Mladen's Price Between 2 Moving Averages indicator for MT4.

As explained by Mladen:
Here is one indicator that can show you when the price is between the two averages

The problem is if you use "raw price" it will be "noisy" (set the "price period" to 1 and you will see what do I mean), so you can use filtering (one more fast average as a smoothing filter) to make it less noisy. If the value is less than 1 and greater than -1, the price is between 2 averages, otherwise it is above (for values 1) or bellow (for values -1) the two averages. That way you can detect when is it "traveling" from one average to another or is outside the two averages, but as far as I see even with additional smoothing it would give you a lot of signals.