Forum Posting, takes some work but can be a good way to grow your online business, by posting on forums you build a reputation as someone with answers, thats of course if you are activley contributing to the forum not just spamming away, that is probably the fastest way to lose credibility in the internet marketing world, and once you have lost credibility I could imagine the internet marketing world would be a hard place to get back on good terms with. The best forum to make a name for yourself is the warrior forum, it has been the breeding ground of many a famous internet marketer. You can even sell your own digital product there.