I recently completed a project for EcoBold.com to help support their mission to plant 1,000,000 trees (that's 1 Million). They are asking for support from the community and came up with an idea to help business owners (and the like) kill two birds with one stone. That is - EcoBold decided to take the million dollar homepage approach and offer businesses (and individuals) a way to promote their business while at the same time planting trees and helping our environment.
Supporting the cause is simple, you visit the million tree project page and select a group of pixels to purchase. Each pixel is 1 dollar and helps plant one tree. After selecting your group of pixels, you are presented with a slide down modal to provide your company's information, things like the url, an image, a tag line, etc. After that confirm your selection, make your purchase and own a piece of history.