The Uniform Server is a lightweight server solution for running a web server under the WindowsOS. Less than 10MiB! It includes the latest versions of Apache2, Perl5, PHP5, MySQL5, phpMyAdmin and ... NO INSTALLATION REQUIRED! NO REGISTRY DUST! Just UNPACK and FIRE UP!
I love it, but I'm really hampered by the new releases of UniServer Zero that cannot be run without administrative rights. Working in a corporation, I don't have admin rights, yet I work on localhost web development for many live projects. Using an older version of UniServer is not a good option since I need to use latest versions of PHP and MySQL as soon as possible.