BOSS
This is the BGI Over SDL Subsystem that consists of a rewrite of old DOS header file/libraries: Borland's graphics.h, conio.h, bios.h. Also includes some support for sound and for mouse. I started this project to support a couple DOS game projects a friend and I were working on many years ago. Here's the page on which I had charted my original progress.
As of 2007-04-01, I have released this as an open source project - but no it's not a practical joke, it was based on this person's request to do so. I'll host the project here for the foreseeable future. If people want to contribute they are more than welcome to send me patches on this aging source code, my email is located on this page. A great first patch would be to send me a Makefile that compiles this thing in Linux... NOTE: I did get a contribution from Jean-Loup Komarower that updates BOSS to compile successfully in Linux. I have yet to review and post that update here...
Source Download
The latest published version of BOSS Library is 0.45. You can download the source here: tar.gz and zip. Unfortunately there are no up-to-date documentation files on the library, you'll just have to look over the source yourself.
Cruft
Aging BOSS Documentation (auto-generated from Doxygen) is available here: HTML and CHM. However, I must warn everyone that the documentation is at least 3 years out of date and contains the old licensing information. To clarify: the library is now released under the GNU General Public License.
I am keeping the download of the binary files available in case people were depending on them, but they are missing a couple things I added in 2005 for Sinasac's Zombie Nightmare project.