Imaginary calculator, the use of which, is sarcastically suggested by others to highlight a person's incapacity in completing a technical task. A secondary function of the term's use can be to convey the frustration experienced when working with such a person.
Brendan: How do you get the final answer in this problem?
Paul: Just use the Infinity Calculator in Excel.
Brendan: What? Where's that?
Paul: You mean you don't know how to use the Infinity Calculator? FFS!