Is MS Index server the best search?

Hi,

I’m just getting into a project to organize a company’s windows explorer which contains literally thousands of folders and sub folders across many layers. The sponsors want to either figure out a perfect way of re-organizing the folders or conversely, utilize a powerful search engine to find data content. Stipulation – budget is next to nil and so I’m looking at using MS index search server to handle the job. Can anyone provide another option or point me to a better resource?

Thanks in advance for the assist.