I've got an adsense account, but currently hardly use it. At the moment I'm currently working as a IT Help Desk Assistant, but also design websites and produce content during the weekends.
I think the most critical success factor is to think how to increase your website's visitors (traffic) . With good traffic, although the CPC is low, but you still can earn good income; with good traffic, you can have the bargain power when you want to sell it to other people; with good traffic, you can earn more by participate various affiliates programs from clickbank or regnow and sell the products/services in your website.
However, for those who still rely adsense as the main income, how to prevent adsense to be banned is a-must-learn lesson. hope my post (in my signature) can help
Since I do not get that much clicks, I have also decided to reduce the number of adsense ads displayed on my pages. It just is taking up space and paying very less amount in return for those huge spaces.
PPC programs like adsense, adbrite and widget bucks are my secondary source of income. I make in the low x,xxx amount each month. It's a lot of work but the extra income has given me lots of freedom and if I ever close my computer repair business down I will still have a great source of income.
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