There a few, good, legit services out there that actually pay for your opinion. These, in my opinion, are the better than aimlessly clicking adverts.
I am a member of a little site which not many people know about. They give me a few surveys every week and pay out in PayPal, gift vouchers, or actual items. They also pay me when I want them to pay me, no waiting each month.
You may not think that I get much from this site, and it's true, I don't. But I am a member of quite a few of these "little, less known" websites. It all adds up. I've just ordered Unreal Tournament III and I used some of the money to pay for a new monitor.
It's a good way to make a little money, if you find the right sites.
Most of the more popular sites give you very little money. I will give you a link to one site which I used to use, and it's a very good system in theory.
You log in, and get a list of ads. You view each ad for thirty seconds and you are credited with $0.01. It's not much, but it adds up in the long run. Also, it's free money, so stop complaining. They pay out in PayPal so you can change the money you recieve into any currency you wish.