I had a university exam where my calculator literally didn't work. I put a note on the paper to that effect and worked out as far as I could by hand without actually giving any of the final answers. Given the test was about knowledge and not the precise answers, I don't think it harmed me any (my grade was over 80%).
I passed my physics classes refusing to evaluate the final expressions, after all that's what calculators and computers are for. I don't feel that had a huge impact on my grades either and my sanity/stubbornness went unharmed.
