It doesn't matter what type of blog you have, or want to have, you can blog about virtually anything under the Sun and still have the potential to make money. How? Easy, just start adsense blogging. Don't let the term scare you off, it's really quite easy. All you have to do is sign up for Google's Adsense program, for free, and they will place ads directly on your site for products and services related to your site. When someone clicks on one of the ads on your site you will get paid.
Now I want to make sure that you have realistic expectations. The amount of money you can earn will vary dramatically based on the topic of your blog. If your blog is about something that is hugely popular and there are a lot of people who are going to pay money to buy ads for that topic, you'll make more with every click. On the other hand, if your blog is about something a little more obscure each click will earn you considerably less.
No matter how popular the topic of your site is or how much Google will pay you for each click, you will need a lot of traffic if you want to make a lot of money. Please don't expect to put some ads on your blog and retire from your full time job. In most cases that simply won't happen. What can, and often does, happen is that you'll make some extra money every single month just by doing what you're already doing... blogging.
If you want to increase your earning potential there are a few things you can do to optimize your Adsense revenue:
Get more traffic. There are a lot of ways you can do that and the processes can be as simple and free or as advanced and technical as you like, it really depends on whether you are online to make a living or just online to have some fun and making some extra cash is just a bonus. For the most part, more traffic to your site equals more money from Adsense.
Leverage your money making potential by setting up many blogs. If you have 10 blogs and each of them is making just $10 a month that comes out to $100 a month. That's $90 more a month that you would have made with just one blog. True, you won't get rich on it but again, it's more money in your pocket for doing what you are already doing... not bad. Now, don't let the idea of having multiple blogs scare you off, there are easy ways you can automate the system to make it very easy to build your own 'blog empire'. If you want to make a full time income online, that's one of the best ways to go.
Adsense blogging is a simple and easy way for anyone to make a little extra cash online. Just by going to Google and signing up for adsense you can make money on your blog. And for those of you that want to make a full time living online, there are many ways you can leverage the power of your ads to really ramp up your earning potential. The bottom line is that it's really all up to you and what you want to accomplish with your blog.