popular methods

1. CPA: There are 100s of different method for this but the most popular methods involve Craig's List, Mass Mailing, PPC (Adwords, Facebook, Adbrite, etc), YouTube and Gateways.
Craig's List Threads:
http://www.blackhatworld.com/blackha...-work-you.html
http://www.blackhatworld.com/blackha...ew-method.html
Mass Mailing Section:
http://www.blackhatworld.com/blackha...ing-opt-lists/
Youtube Threads:
http://www.blackhatworld.com/blackha...y-youtube.html
http://www.blackhatworld.com/blackha...y-youtube.html
http://www.blackhatworld.com/blackha...less-cash.html

2. Adsense: This is a wonderful way to make an autopilot income. Start with keyword research and analyze the onsite and offsite SEO of the top 3 results. You then go onto purchasing a domain and hosting. You will need a website with unique content, high CTR template and Adsense placements.
Adsense Threads:
http://www.blackhatworld.com/blackha...-tutorial.html
http://www.blackhatworld.com/blackha...r-adsense.html
http://www.blackhatworld.com/blackha...h-adsense.html
http://www.blackhatworld.com/blackha...e-blogger.html

3. Auto Blogs: Auto blogs are set and leave. You just set them up and then that it. You put some adsense and CPA banners on it, and it will start bringing you some small amounts of cash in the long run.
Auto Blog Threads:
http://www.blackhatworld.com/blackha...autoblogs.html
http://www.blackhatworld.com/blackha...resources.html

4. Flipping Websites: You can either start from fresh or buy a website that is already made. The easiest is to buy someone else's website. Run over to DP, buy a site that you see you can make better. It could be design, SEO or content. Best website to sell your finished site on: http://flippa.com/

5. Articles: Article are used for so many parts of Internet Marketing. From SEO, to direct traffic for Adsense, to Clickbank affiliating. If you have no investment money, this is certainly what I would look at first. Start buy writing on DP and get a few hundred bucks.
http://www.blackhatworld.com/blackha...es-fiverr.html

6. Affiliate marketing: Clickbank is a great affiliate program but there are tons more than people prefer.
Affiliate Threads:
http://www.blackhatworld.com/blackha...al-method.html
http://www.blackhatworld.com/blackha...y-network.html

7. Joint Ventures: Yes, I'm serious. Your skills + Partners skills = Bank. Or Your money + Partners skills = Bank and vice versa. Do not enter a JV unless you are ready to take a large responsibility.
http://www.blackhatworld.com/blackha...oint-ventures/