I have a friend who asked me how it would be possible to have an application that they use accessible to their other computer inside of their house. The application that they need is in their shop, but they want to be able to do some of the grunt work inside of their house, which is understandable.
My suggestions were: 1. Buy a new computer or find a computer that you really do not use or even a used one on craigslist. Install the application that you need on that computer, and then install some free remote control applications (you can use Windows RDP if the host computer is running a professional version of Windows 7) and have this computer running all the time. You can then remote into this computer and do your work.
2. Install a VMWare on any of your computers and have it always running, and configure the VMWare to have a bridged connection so it is accessible to your network. Install Windows and your application on this VMWare instance and then you can RDP into this Widnows instance and use your application.
3. Install your application on a laptop and take it with you.
I am sure that there are a few other options, but these were the one that readily came off my head.
