Funny you should ask this. I just posted a message about white flecks in my beer in the secondary. To me, it looked like the stuff that had sank to the bottom and I figured must have somehow stayed floating on the top due to surface tension. What stage of brewing are you in? If it's the primary, there's always lots of gunk in there. Did you use irish moss by any chance? It's the first time I used it and the first time I've ever seen the white flecks.
I just used it for the first time in my last batch. It made crystal clear beer, but I think that's where the floating white flecks came from. Beer tasted fine. Taste it... if it's infected, you'll know it by the taste.
Every batch I've made has white stuff at the top....it always looks like an infection to me, but if you get reeeeaaaal close and look, you'll probably find that they are tiny bubbles that conglomerate to form little white blobs. No problemo. My experience, anyway.
Every single one of my brews has had it in the secondary. Its small clumps of tiny bubbles like RighWingNut said. Its the final fermentation stage. I use the amount of bubbles left on top after a few weeks to let me know when to bottle.
At the beginning of the second stage there is always a good amount of clumps of bubble foam. After three weeks or more it subsides to a smaller amount, and this is when I have been bottling. And every batch has been perfect in my opinion.