It's really hard to guess at Amazon's code contributions; I don't know what weird corporate anti-pattern causes this, but I've received patches from Amazon in emails which say "here's a bug fix but don't tell anyone that this came from Amazon", and I know other people who have received similar contributions.
In a more financial sense, they have been generous in supporting my work on FreeBSD/EC2 -- not with cash, but lots of free EC2 usage for development and testing.
In a more financial sense, they have been generous in supporting my work on FreeBSD/EC2 -- not with cash, but lots of free EC2 usage for development and testing.