I'm not sure if this one has already been shared by our members but here is another nice new code from Mladen which I think would be very useful for traders is his Adaptive ATR for MT4.

Thanks to Mladen for creating some valuable tools for the older platform and also releasing the source codes

As explained by Mladen:
This is an adaptive ATR for metatrader 4.

Apart from being adaptive, there is one more deviation in it - it is calculating average range (not average true range). The difference is subtle but it exists. It means that unlike the average true range (that checks if there was a gap when compared to previous bar), this indicator is calculating average range of high to low. And that is it. It is, as it is obvious from previous description, "ignoring" the gaps and that way it is calculating only the "effective" ranges.