This format is used as the color palette format for a variety of operating system image editors. It is used to store font templates in text and graphic editors. It allows you to change color intensity and transparency levels.
The SXW file format was originally created for StarOffice Writer, the word processing application for Sun Microsystem's StarOffice suite. Programs that can open SXW files include StarOffice Writer and OpenOffice.org Writer. To open an SXW file in Microsoft Word, it's usually possible by renaming it as a DOC file.