I have the ES File Explorer and DropBox applications installed on my Revue. (I'm not quite clear on when or how I should use them actually.) A little while ago, I downloaded the PrinterShare Mobile application. I was planning on checking out my local prices on a Google Cloud Ready printer in a few days and as it turned out, the Printer Share app only works free if you have a GCR printer. When I buy the GCR printer, I'll check out the Cloud Print app to see if it's better. After I installed PrinterShare, I just happened to navigate to the DropBox app and it had a PDF describing DropBox. I've spent the list two hours on GoogleTVForum searching for a free PDF reader. I've got some leads, but I haven't downloaded a reader yet. So I was surprised when I clicked the PDF, and was asked if I wanted to download the PDF to an SD card. I figured I needed to buy such a card on Amazon and then plug it into a USB outlet on the Revue. So I was doubly-surprised when the four-page PDF was visible. I tried enlarging the page, as the print wasn't that large, but was unable to. It was then that I read PrinterShare's FAQ and realized I could print a PDF with this app!!! (But not for free, unless I bought a GCR printer, which is probably not going to be less than $100.) I navigated to ES File Reader to look for this mysterious SD card. And there it was! But I have no idea what it is or what to do with it. Is it a large file and should I delete it regularly?