Below you'll find some files that may enhance the experience of the game, and/or let you look deeper into how it works. Some of them are for 'experienced users', some of them can be useful to everyone. Some of them are made by members of the Deus Ex community, some are provided by professional companies:

I do NOT provide support for these files; use at own risk!

Official US version game patch, 1.2

(only for US version of the game).

Kefren's 'DXTool', version 1.42

With this utility, you can tweak DX:IW
and extract texture files from it.

Files to enable surround sound,
provided by 'Arne Bockholdt'.

Read the accompanying
Readme file. In my own
experience, they will work if
you put the files in the game's
'System' folder, without further
tweaking, but this may be
different on other machines.

Windows Texture Viewer by Nvidia.

Read the accompanying Readme file.
Move the WTV folder to Program Files,
then open a .dds file, and choose to
always open such files using WTV.exe.
You can then open for instance my texture
files to have a closer look at them. This can
be useful if you wish to have a close look
at the textures, but don't have access to
Photoshop or other such programs.

.dds thumbnail viewer by Nvidia.

This software integrates with Windows and
enables viewing of .dds thumbnails, so that
if you have a folder full of .dds files, you will
be able to see how they look by looking at
their thumbnails, just as you usually can do
with for instance .jpg images.

Adobe Photoshop .dds plugins by Nvidia.

These plugins will enable you to
read and write .dds files, in
addition to creating normal maps.
Photoshop obviously required.