The ApacheSolr module allows the integration of the core search module with the power of the Apache Solr search platform. Aside from better performance the most prominent feature is the addition of faceted search. In essence it's a user-friendly manner to search for content by filtering on author, content type, taxonomy,... You can try a demonstration on the search pages of Robert Douglass, author of the ApacheSolr module. Now, not everyone has the resources to set up a server with Apache Solr, be it an actual dedicated server to run the software on or the funds to rent one. Luckily, there's also the Faceted Search module that provides similar functionality without this extra requirement. You can check out the demonstration by David Lesieur and see how it compares to Robert's. Faceted Search also has a couple of extra features that make it a worthy competitor. Although the module also uses Drupal's core search functionality, it has a unique concept of environments that allow you to create multiple search instances, each with their own filters, configuration and url. So you could create a specific search for your company's blog posts (filtering on content type "blog entry") and one for your projects (filtering on your custom content type "project" and perhaps a specific author). Another great option is the Related Categories block. This block appears on individual nodes, providing terms related to the node's content. It works as an entry point for a complete search and lure the user into viewing more of your content. One last useful feature is that Faceted Search allows you to display either the search extract (as you would find on a regular search) or the teaser (as you would find on taxonomy listings for example). This is another great way to move away from the classic idea of what we do with search and how we can provide a user-friendly way for visitors to navigate through our content.