Closet Hunt- Layering Bras

One of the things I am always on the look out for is fun bras that I can layer and don't mind if they might peek out of something...mind you, just a peek!  Here's a few that I have been drooling over...

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Love this Stella McCartney for Adidas Yoga Bra, functional and pretty!  Perfect for heading to the studio.

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This T by Alexander Wang Bra is exactly what I'm talking about when I think of a layering piece.  Very chic, and since I'm not very busty, I love the idea of the deep V.  This one is high on the list.

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I received this Spanx bra for Christmas-talk about comfortable!  I love the fact that it's a little longer and it looks great under sheer tops for that reason.

What other great pieces are out there?  Any other recommendations?
J.