Does anyone read blogs?

Friends say I should start a blog. I like to write, and I have lots of wide-ranging interests and ideas. So why not post some of that to the web and maybe make some money?

I find myself drawing a blank about what I'd blog about, though. Who would I write for? What would be their purpose in reading?

I seldom read blogs. I find them boring. With one exception, I don't see why anyone would read them. Seriously, does anyone except your spouse and closest friends care what random thought crossed your mind today?

The exception is blogs about fast-moving domains, written by people who themselves follow the domain closely. Following the blog would be of interest to others who want to keep up with that domain. Indeed, my understanding is that the most popular blogs are about gossip, politics, and specific industries. This is what we used to call "journalism". Similarly, a kind of blog that I can see the value of is a blog about some skill, like "lifestyle design" or getting straight A's in school. Not "any random thought", but "the latest about a specific topic from a very good source".

I hate to shoot down an idea without even trying it. Without a purpose for writing, though, I don't see how to even try writing a blog. Any suggestions?