AWS sorta has something like this already with CloudWatch, but it'd be nice if it was simpler and immediate instead of reactive. I just run a little reserved EC2 instance so my main billing risks are excessive data out or forgetting to renew a reservation and reverting to by-the-hour billing. So that I don't worry about it much I have three alarms that notify me if either "estimated charges > $x for 1 datapoints within 6 hours", or there's "anomalous" NetworkOut over a day, or "there's more than X total NetworkOut over a day", and another alarm that's "NetworkOut > Y for 1 datapoint within 15 minutes" that notifies me and shuts the instance down. I'd like to have a hard cap of "my instantaneous billing running total for the month, not my 'estimate', has exceeded $x, shut everything down" but what's there is something.
I use AWS for a very small side project. I used about $10 back in July, and I don't expect any more costs for several months (aside from S3 hosting).
It would be really nice if I could preload $100 into the account and remove my credit card. I don't have ANYTHING sensitive behind my username and password- except my CC #
I know they are never going to implement this because I'm small potatoes, but it would be nice
For data out I have some alerts set similar to yours to shut down the instance if NetworkOut becomes unusually high—over three different time scales. Since the alerts are delayed, though, I also set up traffic shaping rules in the VM to throttle the NetworkOut to something reasonable so that it doesn't incur a huge bill before the first alert triggers. Officially the VMs have 5 Gbps network links; at that rate you can accumulate quite a large bill in a very short time if the VM starts saturating the link.
