What are some alternatives?
When comparing OpenNebula and OpenStack, you can also consider the following products
Proxmox Virtual Environment - Proxmox VE is an open-source server virtualization platform to manage KVM virtual machines, LXC, software-defined storage and networking, HA clustering, and multiple other out-of-the-box tools on a single solution.
DigitalOcean - Simplifying cloud hosting. Deploy an SSD cloud server in 55 seconds.
Virtualizor - Virtualizor is a powerful web based VPS Control Panel.
Bluehost - Bluehost - Bluehost is one of the largest and most trusted web hosting services powering millions of websites. Join Bluehost now and get a FREE domain name!
oVirt - oVirt is a virtualization management application.
Microsoft Azure - Windows Azure and SQL Azure enable you to build, host and scale applications in Microsoft datacenters.