There are a couple schools of thought on this subject. The first and most obvious is to find a domain name that better represents your blog's content.

Option 1

If you're writing about cars, having a domain like carblog.com would be your best bet. But as you would imagine, practically all of the "good" domains are already taken. This shouldn't stop you in your search though. Now's the time to be creative!

Why go with this option?
One of the advantages you get with a specific domain name is that the keywords in the domain are used as a ranking device for your content. Google tends to think that domains rich in keywords contain more valuable content. As we know, this isn't always true.


Option 2

Create a new brand. Sites like Twitter, YouTube, Google and Yahoo! have all been successful at creating a new brand name. This route is much harder when it comes to promoting your site, but it's much easier to find an available domain name. I did the same with my site when I registered ledfrog.com 12 years ago. However, unlike the big guys I mentioned, I don't have the clout (or the money) to blast my domain name to the world, so I'm just banking on the search engines to rank my content!

Why go with this option?
Get a unique and cool-sounding name to make your own. Once you have a brand, you have unlimited potential for anything you want to do with it.