Gravity preset, Unpack Precomp script + more

@AdobeAE notes some free utilities by Jesse Toula, who has the new tutorial on Custom Shatter Maps. Among the templates and footage for sale are his Unpack Precomp script and a Gravity preset, Quick Gravity, and a separate tutorial.

[Update: didn't check to see if this was the same but Jesse Toula now has a Gravity in After Effects tutorial on Creative Cow.]

There's probably more resources in AE Help, but you can also check out a script palette that's been shipping with AE called Gravity.jsx for a bouncing ball effect. For something similar with expressions, see Dan Ebberts' Bouncing Ball example on MotionScript, and his gravity expression triggered by a marker at Creative Cow (see also Expression example: Animate scale at each layer marker):

g = 1000; // gravitational constant

if (marker.numKeys > 0 && time > marker.key(1).time){
t = time - marker.key(1).time;
y = g*t*t/2;
value + [0,y]
}else{
value
}

Update: see also Better Bouncing in After Effects on a similar preset by Ian Haigh.