If you are looking for a way to increase AdWords activity in your account while keeping click costs low, make sure you test Dynamic Search Ads.
I like to set up a separate campaign for dynamic search advertising instead of just creating dynamic search ads within an existing ad group. I feel that I have better control over the program and potential click costs. Typically dynamic search ads will be about one half of the cost of a regular keyword targeted program.
Dynamic search ads work by using the power of Google Search; Google knows what pages exist on your website and when you set up dynamic search ads, you tap into this power. Google will match a users search query to pages on your website, create, on the fly, an ad title for you and even take the person that clicks the ad to the page that speaks to that specific search by dynamically creating the destination URL.
There are no keywords with this type of campaign and dynamic search programs are really great for driving quality targeted traffic. Using this with ecommerce programs is a must.
One word of caution, make sure to keep an eye on your dynamic search ad categories and know your content. For example, you may want to create a negative category for your blog pages so you are not driving traffic to informational content. You may want to create a negative category for ecommerce pages that show a product out of stock. Just be a little savvy in set up, and dynamic search ads can be a great supplement for just about every AdWords advertiser.