Face book: Do you know Face book is the second most visited site in the world? It has about 80 million members. It is believed that about 30 million members are active. If a site has such a huge traffic, then there will be earning opportunities on this site as well. It's true most members are using Face book as a social site. They use it for meeting new friends all over the world.
Games: It is believed that you can make money playing games on Face book.There are several games over there. You have to learn how to play these games profitably.
Promote affiliate products: Some Internet marketers are promoting products of Amazon, Click bank and EBay effectively and make money. If you have your own product or service, you can promote your business and make money.
Selling your product: If you want to sell your E book or offer online tuition services, Face book can be very much helpful.
Drive traffic to your website: If you have a website, you will be working hard to get traffic. If you learn how to use Face book to drive traffic to your website, sure, you can make more money as more traffic means more money. If you are earning from Google ad sense, you can increase your ad sense income by getting huge traffic from Face Book.
Summary: I strongly believe that there is a lot of scope to earn money on from Face book. But, it's not that easy as many Internet Gurus say. You need to learn several techniques to get real income from Face Book.You have to work hard, work smart with patience and dedication.