If you are building a site that has the potential for information that will never age and remain useful for your audience, you have the opportunity to create what is known as evergreen content. It's important to carry out extensive keyword research before planning any evergreen content for a site like this, as your site could hugely benefit from the proper usage of keywords within such content.
I, too, have always looked at ClickBank as a secondary and even tertiary monetization source. But it can be a great sources of revenue. I linked one of my articles to a related product on CB, and without really doing promotion or anything unusual, I get a few sales a week. Mind you, the keyword(s) for the post aren't that huge either. So, even though the traffic not huge on that post, it still manages to get some sales.
Affiliate marketing is also called "performance marketing", in reference to how sales employees are typically being compensated. Such employees are typically paid a commission for each sale they close, and sometimes are paid performance incentives for exceeding objectives. Affiliates are not employed by the advertiser whose products or services they promote, but the compensation models applied to affiliate marketing are very similar to the ones used for people in the advertisers' internal sales department.