Wren - Offset your carbon footprint by saving rainforests
BeFrugal - BeFrugal is a cashback shopping portal that allows you to receive cashback on every purchase.
Klima - Go carbon neutral
Freebird - Freebird is a cashback and shopping rewards platform that allows anyone to participate at no cost.
Trip to Carbon - A carbon footprint calculation API for travel.
TopCashback - TopCashback names itself the UK’s most generous cashback site. They offer cashback on over 5,000 retailers with a variety of payment methods including gift cards, PayPal and bank transfer.