You can do this using content only products.
Create a category called blog, and make it hidden.
Create a custom category template for your blog, and set the blog category to use it.
Add a content only product (your blog entry), and add it to that category. It won't show in the search results, if it is only in a hidden category.
Using this method, you can't make the blog searchable, unless you want those entries to show up within your regular search results. However, it is a good method for a simple blog without any hassle. We also use a custom 'add comments' area, which uses the built in product review funtionality.
If you want to see our example, just email me.