1) Showcase a new product.
2) Have an online class.
3) Post pictures of customer's using your product or services.
4) Use the blog to post news of sales and post coupons.
5) Have guest experts in your field post to your blog.
6) Spread problem solving solutions.
7) Provide upcoming news about your product or services.
8) Going to a tradeshow? Provide an insiders view.
9) Use the blog as a special club page.
10) Use it as a forum for answering questions.