What is the best application for an ancient computer?

I have a lot of computers, a LOT of them. The garage is full of vintage and rare machines that used to be the baddest workstations back in their day. I love recycling old machines and figuring out what useful work they can still do. Most of the time they are just glorified calculators for basic engineering problems. But what if I wanted to use one of these machines as a tool for making some extra cash? What applications could I use them for?

Today I dusted off an old laptop I bought off of Craigslist for $20. It's a Toshiba Satellite 320CDS that just won't die. It's a great little machine with Windows 98 installed. It's got a 231 MHz Pentium processor, 64 MB of ram, and 4 GB of hard disk space. I can connect a USB port to it to back up my work, and a cheap wireless card that sometimes works. What do I do with it? Write small programs in C, C++, Fortran 77, Perl, Scilab, MathCad, Xlispstat, Elisp, Postscript, VBA, VBScript, Jscript, Javascript, and Euphoria. So that's the calculator part. I also write documents with it. Microsoft Office XP runs on it if you are patient enough. But I think XEmacs and LaTeX make a speedier solution. I would love to publish a novel or short story with the thing one day. Making a cool $600 bucks for a short story would be so awesome considering the initial investment. I love using it, the fact that it's old motivates me to use it for something productive. I'm weird, I know.

And what modern web browser will still run on the thing? Not firefox, not IE. Yup, it's Opera