A start/End origin option would allow one to set where the start and end of a prim is on the prim instead of it always starting at one corner. Mostly just for cubes so you can have hollow objects like this:
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|pretend|
|these r |
|
|spaces |
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... using only one prim.
Of course you can just rotate the round prims for the effect so only cubes would benifit unless there is some advantage to having it on round prims so zero rotation can be kept.