Here at Delphic Sage our web site projects are generally larger scale. For these projects, we either tend use our code base to create a custom Content Management System based on Microsoft .NET or for enterprise size projects we usually recommend packaged CMS solutions like Sitecore.
But sometimes, these solutions are just overkill. Smaller clients with simple web site needs or marketing campaigns that need a supporting microsite demand a simpler solution. For these situations we are using Wordpress as a CMS.
Wordpress is a LAMP (Open Source) based solution whose foundation is as a blogging engine. You can run it on a Windows server (though it has minor some issues that are supposed to be resolved with new Microsoft Server) or preferably on Linux/Apache. With Wordpress as a CMS you can still create really engaging visual designs with the power a data-driven engine that makes upkeep much easier.