A fellow new mum introduced me to soap nuts as a greener way to do your clothes washing.
I got a sample from the delightfully named In a Soapnut Shell site and tried them out - you put them in a drawstring bag or knotted sock in place of detergent and softener and chuck that in with the wash. They're the shell of a fruit (or drupe, strictly speaking) of a tree that grows in Nepal and India, containing the natural detergent saponin.
I've used them a few times and so far so good - they're fine for delicates, cost a lot less than conventional detergents (3p a wash apparently) and you can bung them on the compost heap once they've lost their efficacy in about 4-6 washes. There's no odour so if you like a bit of scent you can add a few drops of an essential oil such as lavender to the softener drawer. And I like the idea of washing my clothes with the shell of a drupe, so much more interesting than Persil and the like.
I'd like to hear from anyone else who's given them a try - how does it work long term?