One of the interesting features in OS X’s standard calculator application is the Paper Tape. Easily brought up by typing Command-T or selecting Window from the menu bar and then choosing “Show Paper Tape,” I have found that it makes Calculator about twice as useful for me than before.
What paper tape does is quite simple, but useful. It is a window separate from the regular calculator which essentially keeps a record of everything you’ve entered in the calculator, allowing you to have a display similar to that on most Texas Instruments graphing calculators that high school and college students worldwide should be familiar with. I have found that the Paper Tape makes me much more inclined to use Calculator when I need to quickly add a lot of numbers together, since I no longer need to worry about having missed one term.
I think that the Paper Tape may have been added in Leopard, can anyone running Tiger or any older versions of OS X confirm this?

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