RalfBrown? maintains a list of software interrupt calls (and other low-level hardware things) on the PC, which is useful for low-level system programming (e.g., WritingAnOperatingSystem?). It is called the "x86 Interrupt list" and documents system, BIOS, driver and application calls (it also contains notes on viruses and gives a nice overview of OperatingSystem history).
http://www.cs.cmu.edu/afs/cs/user/ralf/pub/WWW/files.html
http://www.ctyme.com/rbrown.htm (HTML version)
It is not maintained anymore, because all the DiskOperatingSystem variants (MsDos, DrDos?) are obsolete. Everybody uses flavours of MicrosoftWindows, MacOsx or LinuxOs nowadays. While also Win32 and OS/2 are documented within this list, nobody really makes use of it anymore (except the FreeDos? project of course).
However back in the days, RalfBrownsInterruptList drove development of most PublicDomain and FreeWare? DOS applications and utilities.