> Does anyone know of a device or schematics to build something where I can
> plug a generic PS/2 keyboard into a dreamcast, so I won't have to buy one?

http://www.mars.dti.ne.jp/~tokoya/contest/PS2KB/readme.html

In this page, the author shows a PS2 <-> serial adaper for Wonder
Swan. The adapter uses a AVR micro-controller and a MAX232 level
converter.

This page is written in Japanese. But I think you'll be able to
understand what the author want to say because you can get the
schematic and the firmware source code. :-p

Probably a device driver like pckbd is required because it just send
key codes to the host via the serial port.

> $24.95 is kind of expensive if I can drop $7-$10 in parts at Radio Shack.
> Most of that cost is probably in buying the Dreamcast cable extender for
> the connector itself.

Unfortunately, it may be more expensive than DC keyboard or goods on
the market if you don't have a writer...

----
ikehara