Back in the day, before the dot-bomb, there was a site that did something similar. A few sites, actually. I think one of them was iWon (<a href="http://en.wikipedia.org/wiki/IWon" rel="nofollow">http://en.wikipedia.org/wiki/IWon</a>), which offered points for performing certain actions on various websites. Others followed a treasure hunting model. You had to find certain pieces of content, or perform certain actions, to get points. They monetized by signing up partners (since this generated visits) and advertising.<p>That being said, I think this is an interesting idea. With Foursquare, Gowalla, and others having popularized the "check-in" idea, the market could be ready for this kind of a service again. If you can build a system to prevent gaming, you'd have a good, defensible product on your hands.<p>I think it's definitely worth a try. You can even scoop up some of the previous ideas (treasure hunt, rewards for actions, etc) and incorporate them too.<p>Good luck!<p>[Edited & added some more info below]<p>Ah, I just recalled a few other attributes of the iWon system. They started with a portal page and rewarded you for clicking on certain links. This obviously is different than visiting a website whenever you wanted and checking in - and I think the latter model is better.<p>They also had a time restriction. You could only perform a certain number of clicks a day, and perhaps even a certain number for hour. Those may not stop people who write scripts to game your system, but it's an element you can consider.<p>I'm guessing you've already considered the social aspects of this too, yea? For example, check-ins could appear on Facebook, Twitter, etc. If your system included a friends concept, I could see which websites my friends like to visit, and perhaps go there too.<p>BTW, if you can pull this off, you'll also end up with a great database of user behavior. You'll know who the users are (Since they signed up on your site), you'll know which offers & sites they like to visit, and you'll know how frequently they do so. Not that I'm highly recommending this, but such a list of users could be very valuable to marketers.<p>As the website owner, I'd love to be able to contact my visitors. Some sites may want to offer visitors free content, free stuff, easter eggs, etc. As a marketer, I'd love to know who visits my competitors, or related sites, so I could offer them incentives to use my service instead.<p>P.S. I wonder who'd become the mayor of Hacker News ;-)