One of the most important things in SEO is link bait, or the way that you acquire links to your site. There are many ways to do that like directory submissions, forum posts, submitting to social bookmarks, etc.
Of course besides free ways there are several paid options to link build your site. The problem is that in most cases you have to pay on monthly/yearly basis in order to keep your link alive, or otherwise you will loose the link and the ranking that it is giving to your site.
The solution to this problem came from the permanent link sales. Buying a permanent link always have less risk, and after all a SEO campaign should not have residual expenses but residual traffic 🙂
There are several ways to get permanent links, but as there is no automated solution/marketplace like text link ads, you should search yourself for the best deals. Of course there are plenty of webmaster forums out there that can help you with this process.
Finally I will give you one great deal on permanent text links which comes from webdigity’s donation page. The page is a pagerank 4, and as it links to the top donators web sites it is a good deal for $1 or so 🙂