Helicon Ape provides support for Apache .htacces and .htpasswd configuration files in Microsoft IIS. It literally implements Apache configuration model and nearly all Apache modules in a single IIS add-on, not only making IIS compatible with Apache, but also extending it™s functionality by a number of highly essential features.
Includes following modules: mod_rewrite, mod_proxy, mod_auth, mod_gzip, mod_headers, mod_cache, mod_expires, mod_replace and others.
Features:
Compatibility
modification-free transition of Apache web sites to IIS (including .htaccess, .htpasswd, etc.);
easy configuration of PHP and other Unix-based Web applications on IIS;
powerful, fully Apache-compatible URL rewriting syntax — no rules redesign is necessary.

Security
password protect directories with text or datagbase password files;
comprehensive protection from DoS attacks and hotlinking (content leeching);
all-round web request debugging with HTTP-level web developer toolset.

Usability
powerful configuration editing, syntax highlighting, help, testing utilities in one place;
plain text configurations — no XML, easy translation;
per-site installation without hosting administration participation;

Performance
full-fledged reverse and forward proxy functionality;
drastic server speed-up due to finely adjustable compression and cache functions;
on-the-fly links, headers and HTML body modification.