How to keep your site fresh and alive

Adding “Fresh Content”
Keeping your site up-to-date, fresh and with engaging content will dramatically increase your chances of a higher rank. Search engines like to see new content being created.
Message Boards (Forum Widget):
This generates new content as often as people post, and doesn’t require a lot of effort on your part. Clearly, the more you participate in these discussions, the more likely it is that you will have frequent postings and interesting discussions. In addition, the spiders will crawl your message boards and report its finding back to the search engines.
Blog Articles:
Talkspot has a “Blog” widget. It’s a fantastic way to keep fresh, ongoing content, which can additionally be emailed to people. Frequent “blogging” will really keep the spiders coming back for more. A blog can be on any topic and you can create your own rules.
Have a simple daily one, or a complicated monthly update. Provided change occurs and a site doesn’t become stale, you should slowly continue achieving higher and higher ranks.
Newsletters and Mailing Lists: has robust newsletter and mailing list abilities. Utilizing these tools indirectly affect your search engine results, how it does it is if more people are going to your site after readying a newsletter or blog post you've sent to a mailing list they use traffic as an indicator of a sites relevance on the subject(s) the site is optimized for.
Other Site Updates:
Any site, regardless of content, is able to generate more content about the topic that the site is intended to portray. A business site can post press releases, news, time sensitive promotions, etc. They want to see that a site is changing and evolving. Active sites are ranked heigher than sites that are stagnet and not updated on a regular basis. Search engines assume that if someone is working on it and updating it's more relevant. SEO is ultimately about 2 things; one, to generate more traffic to your site and two, to give people the type of information that they are specifically seeking.