I've searched here and on Google, to no avail, for a tip Craig Anderton published last year, I think, relating to fading a track or clip at the end of a song for a smooth fade out.
 
From memory, the fade begins slowly at first, then changes to fast.
 
When the tip was first published I tried it and found it quite musical, but now, when I need it again, I can't for the life of me remember how it was done.
 
Can anyone remember this tip or point me to it?
 
Thanks and cheers.

Week 146: The Perfect Fadeout
When you want to fade out a song using automation on the master bus, you can either take the time to place nodes exactly where you want them...or you can save much time using this tip for obtaining the Perfect Fadeout. I've been using this technique on all songs requiring a fade for the last couple months, and it works every time. As in, every time! Here's the step-by-step.
 
Open the volume automation envelope on your master bus.
Add a node where you want the song to start fading.
Add another node where you want the song to have faded out, and drag this node down to zero volume.
Add a third node equidistant between the fadeout start and end nodes.
Right-click on the envelope between the fadeout start and midpoint, and then choose Slow Curve.
Right-click on the envelope between the midpoint and fadeout end, and then choose Fast Curve.
 
Done! Of course you may want to do weird fadeouts sometime, but when you just want a song to fade out smoothly and in a subjectively pleasing way, I'm pretty sure this will do it for you. 

Thanks fitzj.
Yes that's the one. Don't know how I could have forgotten it.
 
Cheers