I've been looking over a lot of shoulders the last few months, trying to better understand how my co-workers, family, and even strangers use their browsers. The more I look, the more I find little surprises -- not the "oh wow, that's a totally different way of browsing" kind of discoveries; more like "that's an interesting way to ask the browser to remember a page" or "I would have expected you to use the mouse for that rather than the keyboard."
The takeaway for me is that there may not be a lot of huge differences between how we spend our time in Web browsers, but there are a whole lot of little differences.
I'll give an example and then I'm very interested in hearing some of your examples. Watching someone use a browser last week I noticed an interesting pattern. This person didn't use the back button. Almost every link exploration was in a new tab, even for things like reading the second page of a two-page article. Because this wasn't in a setting where I could easily ask, I don't have a good answer as to what motivated that pattern, but nevertheless it was interesting and it demonstrated to me that even the things I think have one very clear and obvious browser sequence can and are still done using alternative methods.
What patterns have you seen in others that are different from yours? Or, what patterns do you have that you know are different from those around you? And finally, do you think it's an overall good thing or an overall bad thing that there are so many different ways to accomplish similar kinds of tasks in Web browsers?