Restaurant software is also sometimes buggy in the tax calculation area. I had a check at Silks (a very upscale place in Tyngsboro, Mass.) that came, before tax, to exactly $100.00. Since meals tax is 5 percent in Massachusetts, your Ph.D. doesn't have to be from MIT to figure out that the tax ought to be exactly $5.00. Yet for some reason it was calculated as $5.01. I didn't make a big thing about it - I can get the penny back by paying attention to where I walk next time I'm in a supermarket parking lot - but it seemed a bit odd.