Assets - random file display sort paramater

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Is there a random sort paramater for displaying assets images/files? For example, I want to be able to assign a number of images to a field, then in my template display only one of those images randomly.

Would be great to do:

{my_assets_field sort="random" limit="1"}{filename}{/my_assets_field}

I could do this with Matrix, but it seems simpler to just use an Assets field rather than Matrix + Assets just to achieve this.