[glimshe]

XP has vbscript in the command line, giving you more processing power than a standard calculator... Not that people would have time to code, but maybe there could be an advantage to be had. A custom Linux build would be easier to lock down, I think.

[FirmwareBurner]

That's what human proctors/supervisors are there for at exams.

Exams problems are designed to make use of only basic scientific calculator features, I doubt you have the need, or the time, to start sneakily writing VB scripts to try to gain an edge, while the proctors are not looking.