Third Level Push
Websites are typically made up of levels or tiers. The first level is the home page itself. The second level includes your main categories. The third level opens those categories into products, information, etc, and so on. Because second tier pages end up on global navigation bars, this causes those pages to gain a lot of page rank at the expense of 3rd level pages. The third level push essentially takes some of that 2nd tier page rank and pushes it down to 3rd tier pages. To accomplish this task you simply just need to add a "nofollow" attribute to all links on the 2nd tier that point to other 2nd tier pages. Not too difficult really.
From a spider's perspective your global navigation is different on the 2nd tier. The result of all of this is that you get more traffic on your 3rd tier pages, which are typically your product pages and that means more sales! This technique can get more complicated though. You can get even more ambitious and do the same for your 3rd tier links but link back to the home page, not the 2nd tier pages. You can be even more aggressive by nofollow-ing links back to the home page on the 2nd and 3rd tier.
Getting into the more advanced side of this technique can be risky if you don't know what you're doing. Try it at your own risk and only if it makes sense.
