Where I really expect to see Trinity is in slim MiniITX builds that don't physcally have space for an expansion card.
There are plenty of small, half-height Mini-ITX cases around such as the Antec ISK-300 or the Coolermaster Elite 100 which could easily house a Trinity with an active cooler.
If you were trying to do an i3 build with discrete graphics, you're limited to something like a Silverstone Sugo, Coolermaster Elite 120 or even the Bitfenix one that's so large (For a miniITX case).
I was discussing miniITX builds at the LAN last weekend and there's definitely a market for tiny little boxes that fit in places that won't accomodate a build tall enough for an expansion slot.
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