mod_chm is an apache2 module that gives you possibility to explore files 
in CHM format. mod_chm uses chmlib by Jed Wing (http://66.93.236.84/~jedwin/projects/chmlib/) 
to access CHM files. mod_chm is distributed under GPL license.

To install:
./configure --with-apxs2=/path/to/dir/with/apxs2
make
make install

Add the following lines to apache2 configuration file:

LoadModule chm_module         lib/apache2/modules/mod_chm.so
AddType text/chm .chm

Restart apache.
After that you can read CHM file content in your browser by supplying
links to CHM files on web server, like http://you.server/sample.chm or
http://you.server/sample.chm/ .