This article with thanks to http://gamedev.allusion.net/ goes into detail about how the Dreamcast homebrew/emulation scene came about and much more. Heres a bit taken from that article:

“When Sega first designed the Dreamcast, the company was looking to build a high-powered gaming system, but it was also looking to do so efficiently. Unlike the Nintendo 64 or PlayStation 2, the Dreamcast was not loaded with custom hardware. In fact, the Dreamcast is almost entirely composed of off-the-shelf components, with the notable exception of the GD-ROM drive.”

To read the rest of this great article about our scene check it out http://www.elecplay.com/feature.html?article=7110&page=1