How do I redirect all web requests to the same server on my network?

[ray648]

I've got a mac mini that is set up to host an ad hoc wireless network, and has a web page hosted on it. What I want to be able to do is redirect any http requests on that network so that the user is sent to the local site. I know this can be done because this is what a lot of pay per use public wifi hotspots do. You connect to the network, open your browser, and wherever it tries to go it is redirected to the page where you pay for your access. Anyone know how to achieve this?

 

[angelwatt]

I believe they use a proxy for this.