I was polishing my nails with Nfu Oh #66.
As a basecoat I used Sally Hansen Hard as Nails clear. I then did two coats of Nfu Oh, and decided to put a layer of Sally Hansen over the top before putting on the last coat of Nfu Oh.
I had the idea of doing a topcoat sandwich, I ran across this method at The Polish Insomniac here.
It was no suprise when my mani went totally cloudy and dull on application of the clear coat, but what surprised me was that as it dried, it cleared up, there was little loss of the holographic effect.
Here is a pic with Nfu Oh #66 with Sally Hansen Hard As Nails Clear over the top - of all but one nail.
Here is a more obvious shot, the nail that does not have Sally Hansen over the top is the middle finger.
I have also tried this with China Glaxe BFF from the OMG collection, and it seems to work about the same, the holographic effect is a little more subdued, but not lost.