A lot of people who use Swagbucks do it because it often helps save them money in the long run.
If you are one such person, you should check out the Saving Deals blog (dead link). Not only does the author promote Swagbucks and post codes that will help those signing up (which is the only type of code you can post), he also posts coupons and other deals for stores and online sites. Be sure to bookmark the site and visit it often!
The author also provided another way to easily find your Swagbucks ID number. This was updated in the tutorial sections.
Jacob for Swag Central.