Are there different types of emptiness (Śūnyatā)?

Even though emptiness (Śūnyatā) seems like it should just be one thing (concept/experinece/realisation) does it in fact have different types? Can it be categorised in any way? I know Buddhism is very keen on lists. Is there a list of different types of emptiness in any tradition? The motivation for this question is that I remember hearing that there were 32 types of sūnyatā. However I can't remember where I heard this so I'm hoping that this question might cast some light on that issue. If anyone could provide reference to canonical texts, commentaries or other sources about this, that would be particularly good.