I've written a simple, terminal based interface to "sendfax". It pops up a little form with various fields for you to fill in (FaxNumber, FaxCompany, etc), lets you select files to include, and optionally e-mail a copy of your message to someone. It's nothing wonderful, but it works and it's proven useful to people here who are daunted by all the arguments to sendfax.
It's called "sfax", and it's written in Perl. It is available in the FlexFAX contrib area, so you can find it on sgi.com in the contrib area.
There isn't a man page, but a README file that explains how you use it and a sample form file is provided.
Suggestions and bug reports welcome.