The Guinness site is an example: the URL is on the TV and newspaper ads. Guinness have positioned themselves as being quite cool and innovative, so having a net site fits in with the image. The site is quite small, but includes a nice graphic of the product swirling round in the glass, and you can download an attractive screensaver. In other words, they are getting you to spend time putting an advert for their product on your own computer. Because the idea is rather neat, they are also getting people like me to advertise the site free of charge, as I'm doing at the moment. The main drawbacks are that the site only works properly if you have an up-to-date Web browser, and the screensaver is for a PC (so quite a few potential customers will feel left out).