If you make use of multiple cloud providers then you might want to take a look at what ScaleXtreme offers: think of them as middleware for cloud management. Last week the company announced at VMworld a freemium model, offering its Express service for managing an unlimited number of servers completely free? The catch is that you can only manage a single cloud provider; for handling multiple clouds you will have to pay $15 per month per server for the Expert level of service.
ScaleXtreme has been in beta for several months, and has developed a robust offering, complete with its own app store with several dozen add-ons such as apps to install everything from a Java JDK to a full LAMP stack on a cloud-based Linux server.
The service can handle complex provisioning such as dynamic machine groupings, and works with OpenStack, VMware's vCloud Director, AWS and Rackspace. You can browse individual VM file systems, copy files among VMs, monitor each VM, and more. You can see an example of one of its dashboards to download its agents below (click to enlarge).
Everything can be run across multiple private and public clouds, and all of this functionality is cloud-based with no software to install other than your browser and some agents to manage your servers. You can check out some of their screencast videos here that show you how to set things up. (Warning: the audio is subpar and somewhat annoying to listen to.)