What are my options for eco friendly sidings for my house?

I am planning to renovate my house. I have already decided all the major changes that I want in my house. But I am not finding any attractive ideas for sidings of my house. All I want is an eco friendly option for sidings of my house so that whenever someone will look at my house he/she will think of me as nature loving person. So I want help from you guys. Can someone help me with variety of options for eco friendly sidings for my house? I would appreciate your replies. Thanks.