It's virtually impossible to brainstorm a totally original topic to blog about. Instead, your primary and ongoing goal should be to continuously develop innovative content and put a truly unique spin on whatever topic you're blogging about.
You, as a blogger, are a unique individual with your own personality. To set your blog apart, be sure to incorporate your knowledge, voice and personality into your blog. This is one of the easiest ways to set it apart from your competition.
You can also set your blog apart by including proprietary information, publishing extremely timely facts or research, or by incorporating your own unique thoughts, ideas, perspective or expertise into each of your blog entries.
Be sure to research how other bloggers and website operators are presenting similar information, and then develop innovative ways to do it better or in a more unique, attention-getting, and memorable way. You'll want to keep constant tabs on what your competition is doing, plus stay up-to-date on trends happening within the blogosphere.
Another important strategy for creating and publishing a successful blog is to develop content that isn't readily available elsewhere in the blogosphere or on the web. The more unique and innovative your content and the better you target your audience, the easier it will be to build a following.