While I was surfing for info, I noticed that USA.GOV has a perfect Google PageRank of 10. This is probably one of a select few sites to have a perfect PageRank Score.

So, if you want to get a high PageRank, start building links from USA.GOV and the sites it links to. You can follow this for your specific niche SEO needs. All you have to do is find the sites with high PageRank in your field and start building links from that site and the sites that it links to.