libguestfs is a set of tools for accessing and modifying virtual machine (VM) disk images. You can use this for viewing and editing files inside guests, scripting changes to VMs, monitoring disk used/free statistics, P2V, V2V, performing partial backups, cloning VMs, and much more. libguestfs can access nearly any type of filesystem including: all known types of Linux filesystem (ext2/3/4, XFS, btrfs, etc.), any Windows filesystem (VFAT and NTFS), any Mac OS X and BSD filesystems, LVM2 volumes, MBR and GPT disk partitions, raw disks, qcow2, CD and DVD ISO images, SD cards, and dozens more. libguestfs doesn't need root permissions.
abiCloud is a cloud computing platform manager that allows you to easily deploy a private cloud infrastructure. One of the key features is the Web rich interface for managing the infrastructure. You can deploy a new service just dragging and dropping a virtual machine. It allows you to deploy instances over VirtualBox, VMware, KVM, and Xen. It features user management through ACL, infrastructure and network management, an appliance repository, and the ability to easily design virtual datacenters.
UnifiedSessionsManager is a unified and simplified interface for the use and management of local and remote sessions on physical and virtual machines. It provides management of distributed and stacked virtual machines, management of desktops and workspaces on multiple monitors, seamless access to all types of sessions, and support of encrypted connections using SSH.
Karesansui is a virtualization management console with a Web-based user interface that supports Linux servers. It allows virtual machine creation, start up, suspension, snapshot, and CPU/RAM allocation, all from a Web browser. The Xen hypervisor is supported. A RESTful architecture is implemented with HTTP-based APIs.
slkvm is an application to provide some system tools to work with clustering and virtualization. It focuses on depending on as few external tools as possible but to also support as many virtualization technologies as possible. It works in a cluster environment where heartbeat runs virtual machines of nodes that have failed. It builds an "unheaded" cluster to avoid having a clear point of failure. It is able to build a two node cluster with everything redundant. It avoids compiling a new kernel or newer version of applications, so you can benefit from Debian security updates.