I bought a "one of a kind" dress for 50% off. With various coupons it ended up being just $20+. It looks pretty average, but what I love is the cut out opening at the back. The only problem is that it was obviously not tailored to fit me. The front comes down wayyy too low. I went in search of something that I could put/ sew underneath so that I wouldn't look scandalous and the dress wouldn't be "cheapened" too much by. Thus, I stumbled upon the Clip on Cami.
One thing that you have to note is that it is a free hanging piece of cloth. To make sure it doesn't make odd shifts, I suggest taping it to your dress or something.
The dress looks better than this, but it was hard to get a good angling while cam whoring. It is stiched oddly such that the breast area ends up looking kind of pointy though. I will have to make adjustments- perhaps bringing the fold all the way up.