Abyss (http://www.aprelium.com/abyssws/) has two available versions:

Version 1 is only 112 KB and uses a single configuration file and a 
key file. If you get asked for a license, use the data in the key file. 
You can delete all the other files that come with it. The configuration 
file is in "ini" file format. Deleting the other files means you lose 
your nice graphical configuration console and have to manually edit the 
configuration file -- but it makes for a very small footprint! 

Version 2 is 309 KB (but UPX can pack it to 151 KB). You can delete all 
other files that come with it. The configuration file is in "xml" 
format. It will create the configuration file and a "persist.data" file 
when it runs. The configuration console is built in to the executable, 
so even in this small footprint configuration you can use your browser 
at port 9999 to reconfigure the server.

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This script is designed to be used with the free Abyss web server. 
Abyss supports HTTP/1.1, CGI/1.1 scripts, Server Side Includes (SSI), 
and user access control (HTTP authentication/password protected files). 
Adding PHP or Perl support is a matter of a few clicks. 

If you put my "abyssws.vbs" script in the same folder as the 
"abyssws.exe" file, you can drop a folder on the script and it will 
shut down the Abyss web server and re-launch it with your folder as 
the new web root. If you're like me, you'll set up a right-click 
association on folders so you can right-click to launch the script 
with the selected folder as the argument. If you don't put the script 
in the Abyss folder or you don't pass it a folder as an argument, the 
script will prompt you for the data it needs.

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Eric Phelps
http://www.ericphelps.com
Script released into the Public Domain.