Webmasters are constantly in search of new and creative ways to get backlinks to their web sites in order to improve their rankings in the major search engines.

One free, easy way to get backlinks is to monitor forums where people are discussing your areas of expertise. This is really easy to do with Google Alerts.
Simply create alerts for each of the major keywords in your industry, and set the alerts to monitor "discussions" only.

I personally recommend you use an RSS Reader to keep track of these alerts, which is a lot easier than keeping track of email notifications. Google even has a handy built-in RSS reader that you can use if you don't already have one (thus the "view in Google reader" link in the image above).

How this works is simple: each time Google finds a new discussion that is related to the keywords you specify, it makes a note of that in the RSS feed. You can then scan the feed for threads where you can jump in and respond. Most forums let you have a keyword-rich link to your web site in your signature, and so you get free links by joining in these discussions. Those links help your ranking in the search engines over time.

Doing this also establishes you as an expert in your field at these forums, which at a busy forum can be just as valuable as a #1 ranking for your keywords. Not to mention the direct traffic you can generate from your signature links.

How many threads will Google find that you can respond to?
Well, as an example, the "Discussions" alert for "internet marketing" over the last ten days has generated 350 question threads on 140 unique domains. By "question thread" I mean a thread whose title is a question (e.g. "Where do I find a list of blogs to submit comments?" — that's a real thread). The question threads are often the best to respond to, since they establish your expertise, but you can, of course, respond to any thread that you feel you can contribute something to.