Well, I'm not going to comment on the ads that appear on this site too often. In fact, I haven't even looked at where most of those links go. But one that does appear frequently is worth a second look: it's the Australian Government's swapit.gov.au site.
Why does this one deserve another look?
It's part of a secret government conspiracy. (OK not-so-secret, even I know about it.) Someone in the government believes that if they can get Australians to eat healthy food and exercise more, we'll have less "lifestyle" diseases - those forms of diabetes, heart disease, cancer, etc caused by the way we live our lives. And here's where the payoff for the government is - that means it would take less money to maintain our health system, or the same money could be used more efficiently and we'd have shorter waiting lists.
I'm not big on governments interfering in our private lives - but I think this is one scheme we should all buy into: because we all benefit personally. Firstly, our taxes pay for that health system, so we have an interest in getting the best possible use for our money. Secondly, I don't think any of us want to have a preventable disease. (I find I'm miserable enough with the disease I have - and I haven't done anything to feel I deserve it. It would be terrible to think I had caused being sick.)
So let's all get patriotic on this one: support our government's plan. Let's eat our veggies and get off our butts - for Australia (and to protect our own hides.)