This is a pretty straight forward concept and it involves offering space on your website for others to place banners. You can sell space independently by contacting potential advertising partners or advertising it within a page on your website, or you can through a third party broker, such as Buy Sell Ads.

Advantages: Selling advertising space is a very easy way to make some good money, both if your blog is bringing in large volumes of traffic or smaller volumes. If your blog is within a small niche and doesn't necessarily have a huge amount of monthly web traffic, you can offer fixed costs for a month's worth of advertising.

Advertising partners that are looking to target a very specific audience will often pay well for it, even if the total reach isn't particularly large - it's often more about relevance to them.

Alternatively, if your blog brings in a lot of web traffic, you can sell ad space based on cost per impression. You'll often make a lot more cash out of this method of advertising when compared to the likes of AdSense, plus you can also get the chance to build a relationship with your ad partners and negotiate long-term commitments.

Disadvantages: Although setting this up within the likes of Buy Sell Ads is relatively quick, you're not guaranteed that anyone will actually buy advertising space from you. So, whilst the profit margins may be higher, you may need to do a little more promotional work to actually secure a buyer, which some blog owners don't like doing.