flpsed is a WYSIWYG PostScript annotator. You can't remove or modify existing
elements of a document, but flpsed lets you add arbitrary text lines to existing
PostScript documents (PostScript is a registered trademark of Adobe Systems
Incorporated). Added lines can later be reedited with flpsed. Using pdftops,
which is part of xpdf one can convert PDF documents to PostScript and also add
text to them. flpsed is useful for filling in forms, adding notes etc. GsWidget
is now part of flpsed.