[C] I am using Q386 3.65, a math accelerator and coprocessor emulator for 
386SX and higher machines. (Copyright Quickware) It works nice. (e.g. with
Mathematica) You should be able to find it on any SIMTEL mirror in the
directory mathcopr. The name of the newest version seems to be
q87_371.zip. I do not think that there is any possibility to plug in a
real coprocessor.

[C] Date: Fri, 17 Jul 1998 09:34:20 -0600 (MDT)
From: bgeer 

I am using a fpu emulator for DOS/Win3/Win95 which can be found at:

        http://www.delorie.com/djgpp
        (see below for details)

DJGPP is a port of the Gnu toolset to M$ OS.  It is free.  It includes
gcc & g++ compilers, ar, make, gdb debugger, bash, grep, less (more,
only different:-), diff, df, du, & all the vastly more useful tools us
Unix'ophiles have come to know & love.  Specifically for DOS/MSWin it
includes cwsdpmi (DPMI services) & go32 which enables all programs
compiled w/ gcc & g++ to execute in 32-bit mode on DOS, Win3, Win95,
WinNT.

I use this toolset on my Aero & have absolutely no problems with it.
My most notable project is developing access functions to drill into
Clipper databases for improved data query.  With very very few
#ifdef's the exact same code compiles & runs on DOS/MSWin & Linux.

I've found that my programs run 5 to 10 times faster on Win95 in a
bash window than in a DOS prompt window.  

 >  How about giving us a clue as to where to look on that site?
 >  Or maybe even, (dare I ask?) a filename or a closer URL??  :^)

Oh, where's your sense of adventure?!?!?

[Just kidding...]

Ok:
    djdev201.zip  contains  bin/emu387.dxe & bin/go32-v2.exe
    djlsr201.zip  contains    [sources]
    csdpmi3b.zip  contains  bin/cwsdpmi.exe

Newer versions may be available - I downloaded this over a year ago!

Yes, there's lots of stuff there...but it adds up to a mere 63Mbytes
of stuff if you grab everything including sources & all of emacs.
Last time I installed a Borland or Microsoft C++ compiler it added up
to more disk space & didn't provide cross-platform compatibility.