The Dude - MikroTik is a Latvian company which was founded in 1996 to develop routers and wireless ISP systems. MikroTik now provides hardware and software for Internet connectivity in most of the countries around the world.
amon - Self-hosted server and app monitoring tool
Pandora FMS - Pandora FMS: Opensource monitoring software
Cloudlytics - Analyze Your Amazon S3 & CloudFront Logs.
cStatus - Monitor and scan a network.
S3stat - S3stat is a service that takes the detailed server access logs provided by Amazon's CloudFront and Simple Storage Service (S3), and translates them into human readable statistics, reports and graphs.