Most companies that launch or rapidly increase their use of virtual desktops do it to cut their support costs or increase security. Many are now also considering virtual desktops as a way to migrate to Windows 7 with a minimum of cost and hassle, according to analysts. \nBut sometimes, Mother Nature provides her own impetus for virtualization. A major disaster led the University of Texas Medical Branch\u2014a sprawling campus of hospital and office buildings in Galveston plus a spray of clinics and smaller facilities all over Texas\u2014to shift virtual desktops from a fringe technology to its main platform. \n"We realized after Hurricane Ike (in Sept. , 2008), when people were coming in here with PCs that had been flooded out, asking us to put them in a closet so they could use them remotely, that that was ridiculous; we didn't need to be doing this," says Landon Winburn, Citrix systems administrator for the University of Texas Medical Branch. [ For timely virtualization news and expert advice on strategy, see CIO.com's Virtualization Drilldown section. ]Hurricane Ike, which had already battered Cuba and gained strength in a westward trip over the warm water of the Gulf of Mexico, swept north, coming ashore at Galveston at 3 a.m. Sept. 13, 2008, with winds up to 110MPH, damaging three quarters of the houses in the city before moving on to ravage the rest of East Texas. It killed 72 in the United States and caused $29 billion in damage before it eventually blew itself out in northern Arkansas. \nWith the hospitals and clinics frantically busy treating the injured, lost and homeless, UTMB's IT crew had to get as many data and applications online as they could in the days following the storm. \nRather than rescue and then maintain each of the PCs and servers damaged or drenched by Ike, Winburn and his colleagues bought 100 licenses for Citrix Systems' XenDesktop and hosted the rescued machines on Citrix servers. \n"We converted a lot of PCs into virtual machines, and we no longer had to keep running to individual offices to work on them," Winburn says. \nThe newly virtualized systems weren't quite as simple to support as the 2000 machines UTMB had already set up to use more traditional Citrix Systems shared virtual desktops as part of a 2005 migration to an electronic medical records (EMR) system. But they were easier than sending technicians out to troubleshoot hardware problems in remote, storm-ravaged locations, Winburn says. \nUnfortunately, the same setups and requirements that had satisfied the medical departments and most of the branch offices, most of which were won over because 30 or 40 users could work happily on a single T-1 with a Citrix setup, couldn't meet the needs of the other departments. \nEven extending an implementation of performance- and environment-management applications from from AppSense\u2014which cut login\/logout times to a few seconds compared to as much as a minute\u2014didn't help get most of the 6000 to 7000 PC users in UTMB's research, academic and business departments on board. \nOne big problem: they couldn't run the applications they wanted and didn't like the shared operating-system environment, Winburn says. \n "The terminal servers people were using Windows Server 2003, but some people needed applications that wouldn't run in a shared environment, or had to run on Windows XP," Winburn says. \nThe solution was to give those users dedicated virtual machines that could run a separate operating system and even separate applications without affecting the rest of the end users, because each VM was isolated from the server and was erased and relaunched from a master image whenever the user logged off. \nThat worked well enough to satisfy users whose machines were waterlogged and to migrate many other users to virtual machines; but it wasn't enough to get whole departments on board with virtual desktops, Winburn says. Sticking Point: Peripheral Connections\nThe sticking point was users such as nurse managers, researchers and other users who have to connect their machines to peripherals such as printers, bar-code readers, lab or diagnostic equipment and other specialty devices that, until XenDesktop 4 shipped a few weeks ago, the Citrix client software couldn't support. \nIt sounds silly to say you can't virtualize a system because you can't plug something in to a USB port, but it's a big problem for anyone who has to print something too confidential to run on a shared printer, or has to use any special-purpose local device, according to Andi Mann, head of systems and storage-management research at Enterprise Management Associates (EMA). \nFlaws in the end-user experience\u2014which included things such as the lack of graphics support, USB and other PC-friendly technologies\u2014were the No. 1 user complaint and No. 1 organizational barrier cited by clients responding to a poll EMA released in September. \nA feature Citrix calls HDX\u2014which supports both peripherals and graphics applications such as Flash that are designed to run within a browser on a local machine rather than from a server\u2014expand the range of end users UTMB can satisfy with virtual desktops, Winburn says. \nVMware's View desktop virtualization software does not currently provide the ability to plug a USB device into local hardware and have a VM-based desktop OS recognize it. Its ESX1 4.0 server does allow the creation of USB ports, but only for USB devices that can communicate across an IP network. \nHP announced its virtual desktop infrastructure products will also provide that support. \nThe ability to support local peripherals and graphics is winning over more PC users, but UTMB won't reach what Winburn expects will eventually be a 50\/50 split between virtual and real PCs until end users are able to install their own applications and have them available through the network as if they were running on local PCs. \nAppSense has developed way to be able to store desktop applications within end-user profiles, however, and plans to release the ability sometime next year as part of its suite of add-on products for Citrix and VMware desktop virtualization products, according to Martin Ingram, VP of strategy for the company. \n\nIt looks as if UTMB will eventually virtualize about half its total complement of client machines, which will cut both its support and hardware costs drastically, and make life much easier for the 30 or so desktop-support staffers within the 300-person UTMB IT department, Winburn says. \n"With thin clients, the number of devices a technician could support went through the roof," Winburn says. "The cost model around thin clients is just so much lower, it's just amazing. Cost-per-seat for PCs is about $30 per month, versus thin clients that are more like $20 per month, and that includes the hardware, software, network, everything to support that device." \nFollow everything from CIO.com on Twitter @CIOonline.