My work involves looking up a lot of things online, so I keep multiple windows open and just switch between them. I request more work so often that I think I'm beginning to annoy them, so they can't really blame me for browsing some websites/webmail once in a while. Still, it looks inappropriate when I do so I try to keep it hidden.
I've considered writing an RSS reader in Excel or whatnot to keep it less noticeable, but never got around to it.