Sure I do this all the time! And with tabbed browsing (in Safari or Firefox) the thing sometimes goes out of my control. I go to some starting-point website for my day to day mac-news search (macbytes.com) and open almost every entry in a different tab, then start to close the frontmost and read everything, and sometimes even the news themselves make me open new tabs of websites related to the item, so I end up having a queue (FIFO ^__^) of things to look at, and I can't stop without ending it.