E-mailing a script?
PDF is a good option, but converting your script into an RTF, and then e-mailing it, will preserve the formatting no matter what the recipient uses to open it (.rtf files can be opened on almost all platforms and with lots of different software).
PDFs preserve formatting too, but Adobe Acrobat costs money; the word processor you already have can probably convert your document into RTF. RTFs can also be edited, which can make them better than PDFs for a work in progress.
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