According to NSF, you can use your "text editor" to modify the form so that it
will print with your information filled in.   You need a postscript printer,
and be sure to use the forms with a .ps extension.

This is on my list of things to fiddle with, so I can't say how simple (or
not) the process is.  Not nearly as much fun as MacInTax, I'm sure.  Maybe
somebody else knows?

-Marcia Zuzolo
Indiana University
xxxxxx@indiana.edu