Create a government operating system using open source software. Based on Linux or BSD. The cost savings for the Army alone is about $85M+ per year for Windows, I dont what more for MS Office, Anti-virus etc. A standard desktop with office suite, internet browser, anti-virus, PDF, disc burning etc is easily attainable with open source. There are plenty of Linux Distro's and several BSD based that prove the point. Add some built in security features and defaults for govt use. This would cover 90% of government workers. For the science and R&D workstations (that arent already using them) there are plenty of packages available for computation etc. There will be some applications that require windows and special software. But thats the same as now. Why should we keep the current system of putting 90% of workers (who only require basic machines) with software that costs millions->billions and a few special machines (servers, scientific etc) that run low/no cost software. Lets flip the equation so 90% are low/no cost and only a small percentage spend money on software and you can save tons of money.
Additionally- there is also an added benefit for open govt. By shifting govt to open source platforms and standard open formats we can ensure that govt files and documents are available for everyone and will always be in the future. MS already change dthe standard file format for word from .doc to .docx. What will we do 10 yrs from now when they unilaterally decide to depricate .doc support? The govvt will be forced to spend more money converting the files or just loose them. Use of open formats solves this. Additinally it is unfair that the govt requires use of MS formats in many instances. Many bids and proposals state that they require MS .dco format in order to be considered. It is wrong for the govt to require a business or citizen to purchase a product from a single vendor. (It is also wrong the number of govt sites that require IE to work)