I did acid a number of times in my college days. It definitely will keep you up for a while, so don't plan on sleeping until it wears off -- at least 8 hours.

But I can't say that it ever affected my dreams in any way that I could tell, nor did I ever have flashbacks. Perhaps I was just lucky. Of course, I used to smoke a good deal of weed back then too, so my dream recall was probably not very good to begin with.