I've just spent an hour looking for an ebook reader specially designed for reading scientific (math) documents and multiple file formats like pdf, djvu etc but from what I read from reviews and feedbacks,  only the Ipad fits the bill. 
The thing is I already have a laptop and buying an iPad would be surplus to my needs and quite expensive too, given I only need an ebook reader. 
So I was just wondering if such an ebook reader exist and if not ,when are the Ereader companies going to realize that there is a market out there for academics/ students/ professionals ?