I run a website called 'Help From Home' http://www.helpfromhome.org/ which provides information on easy, no commitment micro-volunteering opportunities that can all be performed from the comfort of a person's home. Almost all of the 450 plus actions listed on the site will cost nothing or very little to complete and take no more than 30 minutes to accomplish. Some can even be performed in under 10 seconds without getting out of your favourite chair or pyjamas!
There are 3 categories of positive actions to choose from, one of them being 'Green Volunteer Actions'. I scour the web collating grassroot initiatives that provide actions for people that can be done from a persons own home, whilst still dressed in their pyjamas.
I believe the opportunities listed on the website really can make a difference and if you do visit the website, I'm hoping you'll be able to see what good there is that can be done ….. dressed just in your pyjamas!