Making a calculator isn't hard at all, since JScript already has very powerfull math functions. Buth adding a tab there, and make the tab work will be lots harder.
A way to do it, is to use child windows: one for the extra tab (like the timer in the Timezone script, but placed somewhere else) and one for an editing panel with a toolbar and a message box. It
can be done that way, but I only wonder how the math formules will be displayed in the message box.
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