banner-for-banner: If you run 10,000 of our banners, we will run 10,000 of your banners. Since we get 10 million pageviews per month, that might be a lot more than what you do. So tell us how much traffic you get, put a permanent banner on your site and we will run your banner for that many impressions. However, if you make a thread about your web site, and the banner we are running here links to that thread instead of directly to your site, we will give you four times as many impressions.
mail-for-mail: We currently have 30,000 people on our mailing list. If you have 3000 people on your mailing list, then we will trade you ten mentions of our stuff for one mention of your stuff. And, if our mention of your stuff goes to a thread at permies (which, of course, is about your stuff and contains links to your stuff) then we will do a 4-to-1 exchange.
blog-for-blog: If you make a big blog about our stuff, we will create a big thread about your stuff.
icon-for-something: We are very proud of our new social media icon and hope to see it next to all the other social media icons on all sorts of web pages that are keen on permaculture. We are so keen, that we would probably be willing to trade stuff for it.
Maybe there is something you wanna trade that isn't listed here? We might be up for it. Contact gir at richsoil.com to see if it might fly.