You mean affiliate like.. sale products for a company, like you put one of there ads and they pay you if what ever you helped them saling worked out ?
One good thing is if your site is 'impressive' or.. a reliable source site, if your users really like you and trust 'your word' you can affiliate with everything, since they (your users) are going to be like "hey he said its cool... so it must be cool !"
Suggestions : hosting companies... template sites... anything that sales on web, or also ecommerce sites that sale LOTS of products, like have a spot for them only and the product changes all the time.. like an ad