Global warming: how one can make a difference

I've joined the cause "Stop Global Warming" on Facebook
but I haven't thought of what I'm doing to stop it. It may sound silly that one can make a difference. It most probably is silly to think that a huge difference can be made. But who cares? I can do something. And who knows, maybe someone else randomly reading this post might get impressed and start doing it also and... the effect might be multiplied.

So, let's see what can be done in general and what I can at least do:

At home

Me: 7, 9 (recycling in general), 10 (walking, less taxis)

At work

Me: 1, 3, 4

Outdoors

Me: 1, 2, 3, 4, 5

Some options are not applicable, others - not currently able to do. But anyways, I do make a difference, don't I?