How can I script an alert for when my Amazon Web Service usage goes above a certain amount?

Question

We're using S3, SimpleDB and SQS on quite a complicated project.

I'd like to be able to automatically track their usage, to be sure we don't suddenly spend large amounts of money when we didn't intend to (perhaps because of a bug).

Is there a way of reading the usage figures of all Amazon Web Services and/or the current real time dollar cost of an account from a script?

Or any service or script which provides alerts based on that?

Answer 1

Amazon just announced that you can now "set alarms for any metric that Amazon CloudWatch monitors" (CPU utilization, disk reads and writes, and network traffic, etc). Also, all instances now come with basic monitoring for free.