Cloudlytics - Analyze Your Amazon S3 & CloudFront Logs.
Checkmk - Checkmk - the software for effective IT monitoring
Qloudstat - Analytics & monitoring for access logs in Amazon S3, Amazon CloudFront, Google Cloud Storage and Rackspace CloudFiles (Akamai CDN)
Zabbix - Track, record, alert and visualize performance and availability of IT resources
OverOps - Know why Java code fails in production. Get the full Java source code and variable state for every error. Reproduce and Fix critical issues in seconds.
Trafikito - Monitor CPU, RAM... or output of any command and make API call on event, default is email messages.