Quoting from the Citrix Press Release:

Thinstall, the leader in portable application virtualization, and Citrix Systems, Inc. (Nasdaq: CTXS), the global leader in access infrastructure solutions, today announced the availability of the Thinstall Virtualized Citrix Presentation Server™ Client.  By virtualizing the widely-used Citrix (ICA®) access client with Thinstall technology, Citrix and Thinstall now provide an easy to use, powerful solution for end users, ISV partners, and corporate IT organizations that enables immediate access to Citrix Presentation Servers via a secure USB key.

Thinstall virtualization solves a significant problem in deploying USB applications (in this case the Citrix ICA client) by completely eliminating installation and changes to the host PC. Without virtualization, applications may not run from USB devices because installers need elevated administrative privileges to write system files and registry keys.  Additionally, applications may leave behind sensitive files on unsecured computers.  Thinstall eliminates these critical problems for corporate IT users, making the Citrix Presentation Server Client instantly and securely available on any PC.

“Previously, end users needed to carry a laptop when they went on the road to have access to their corporate Citrix Presentation Server environment,” said Jonathan Clark, Thinstall President and Founder. “With Thinstall, the Citrix Presentation Server Client can be launched from a locally running Internet Explorer session without elevated security privileges. Thinstall enables end-users to access their corporate Citrix servers from any PC in the world without installing ActiveX components or the Java runtime. Also, Thinstall secures the access because session data, browser history, and temporary data files are loaded and stored from the USB drive, never leaving behind sensitive corporate data.”

“Citrix is dedicated to expanding our Access Platform by enabling our partners,” said Chris Fleck, vice president of platform development for Citrix. “USB applications integrated with two factor security devices are growing quickly in popularity with our enterprise customers. Thinstall has a unique, solid virtualization solution and by working together, we have provided both our solution partners and enterprise customers with a Presentation Server Client that they can bundle with these new applications to provide secure access to any Citrix environment.”

The Thinstall Virtualized Citrix Presentation Server Client provides the following features and benefits that are ideal for use with USB drives, remote access, and mobile users:

• Instant Citrix access without installation – The single Thinstall compressed EXE enables the Citrix Presentation Server Client to be carried conveniently on a USB key drive or CDROM and runs regardless of what is – or isn’t –already on the host computer.  This eliminates technical support hassles and makes Citrix access easy for mobile users.
• Works on locked-down PCs – Administrator-lever user privileges are not required because the Thinstall Virtualized Citrix Presentation Server Client does not have to be installed or anything modified on the host PC,  allowing users to have universal access anywhere they go.
• Sensitive information is kept secure – While running under Thinstall, Internet Explorer browser history and temporary files are loaded and stored directly from the USB drive ensuring no trace is left behind.  As well, Citrix Presentation Server client configuration settings are loaded and stored directly from the USB drive preventing the user from accidentally leaving behind their login name, password, or session cache data.

The Thinstall Solution
Thinstall enables the deployment of software applications without requiring installation, system modifications, or elevated security privileges. It allows software to be delivered and updated in an isolated environment ensuring the integrity, stability, and security of the host file system and registry.  Thinstall works completely in user mode with no device drivers, which means it can run on all versions of Windows 95+ without Administrator Rights. The Thinstall Virtual OS technology component is less than 300K on disk, occupies approximately 1 MB RAM at runtime, and has neglible impact on memory consumption and CPU performance. Applications can be packaged without any source code changes for use with a USB key or other distribution method.

“With this partnership, Citrix customers and partners can utilize Thinstall’s advanced technology for any Windows platform from any portable storage device,” continues Jonathan Clark. “Citrix is a compelling example of how virtualization changes how business think about software. With this partnership, Thinstall is able to broaden our reach to more enterprises.”

The Thinstall Virtualized Citrix Presentation Server Client was released in February 2006 and is available for download at http://www.citrix.com or http://www.thinstall.com.