Your iPad can do that.
I work in a small federal agency where almost all our work is law enforcement sensitive. As a result I have to use a special USB key in a windows environment to connect to my work computer.
The nice thing is that I get every functionality, including law enforcement databases on that system without leaving a trace on the external machine. The company that supplies the USB key makes a Mac compatible version, but the feds haven't bought it yet. Maybe someday.