I love my cycling and although I've not been able to do it for a while due to injury (3 torn ankle tendons -2 right, 1 left), but for others it's their only way to get to medical treatment, get produce to market and collect water, a great way to help is recycle old bikes and there's a great website:

Bicycles For Humanity - Australasia
Bicycles For Humanity - Australasia

Bikes for Africa
I'm hoping to get a copy of Bikes for Africa on DVD for Christmas to see more about what the guys are doing.
Bikes for Africa - About - the DVD: Order the DVD - Bikes for Africa

Bikes help a lot of people out of poverty in Africa and this is a brilliant idea!