Oh yeah, and you can also create a mirrored copy of an object by using those corner grips as well - to do that grab a corner and drag it all the way over to the opposite side of the object. There will be a snap point there and if you snap on to it, it will produce a mirrored copy of your object same as doing the Transform/Mirror command.

Also if you are scaling from the center, there are mirror snap points at the other 3 corners to enable an exact "in-place" type flipping or mirroring.

- Michael