Humble Bundle is known for its cheap bundles which allow buyers to donate to charity and support the developer and a noble cause all at the same time. That isn’t the only thing they are known for – they have been quite generous with distribution of free games too! The next game available for free on the Humble Store is Sins of a Solar Empire Rebellion.
Just head over to the store, hit the checkout button, and redeem the key on your Steam account. The offer is valid only for 48 hours, so it’s best to redeem it while Humble still has keys for it.