1. Build up popular free software - eg b2 Evolution.
2. Contain multiple links back to your site that are big keywords (eg - web hosting)
3. Due to lots of backlinks (all in the footer while having no ‘context’ with web hosting combined with your initial authority (almost 3 million backlinks according to Yahoo), rank very high for keywords like ‘web hosting’
4. Build an absolutely crap page that is nothing more than a bunch of affiliate links.
5. Profit massively.

For all this talk of how smart Googlers are and what not - this is just one example of a crap site using footer links to rank very high for a very competitive keyword. You will find the exact same in all the big keywords.