I was reading the 3D forum [link] and someone posted a topic about tips and tricks. I threw a quick little MEL tutorial up on looping, and thought I'd post it here as well. I don't know if it'll help anyone, or if anyone cares really, but here it is:

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If you need to set an attribute across many objects which doesn't show up in the channelBox (like say 'inheritsTransform' or 'displayHandle' you can set them all with one line of mel.

Select the objects you'd like to effect, then:

for ($target in `ls -sl`) setAttr ($target+".inheritsTransform") 0;

The above is a quick example of a mini loop such that each object inside the loop is refered to as "$target" when its it's turn in the queue. If you had more than one operation you wanted to do on multiple objects, you could use "{}"s to contain your commands such that:

for ($target in `ls -sl`){
setAttr ($target+".inheritsTransform") 0;
setAttr ($target+".displayHandle") 1;
}

The above loop would set inheritsTransforms and displayHandle attributes for everything selected.