Open744 is a wrapper for the Aerowinx 744 Precision Simulator (popularly known as "PS1", a DOS flight sim) that lets you run the sim under Linux or FreeBSD without a DOS emulator.
SourceForge project page
If you're looking for 747IPC/WinPS1, the predecessor to Open744, find it here.
As of Open744 release 0.9, Microsoft Windows 2000 and XP are also supported, using the MinGW and DJGPP development tools.
Required libraries are:
Get Open744 from SourceForge !
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.