I recently had the good fortune to come across money4blogs.com
Money4Blogs is a simple way of achieving additional revenue for you blog by using text links as adverts. It is a really simple process to signup, even I found it quite straight forward. Visit Money4Blogs, enter you name , address, url and blog PR, simple as that. Within a few hours I had received a response from a chap called Mike, who is both business like and easy to get on with. At the end of the day he offered me a fair and reasonable amount for a link for a six month period.
I have yet to find a better way to get some revenue to pay for all the hosting and other blogging costs.