[ics]

Jekyll and Middleman have already been mentioned but another is nanoc [http://nanoc.ws/] which I like because it is not so blog-centric. You can get a good overview of how it works relative to what you want just by reading the Rules doc page [http://nanoc.ws/docs/reference/rules/], but essentially it does nothing by default except dump your HTML input into the body of the default layout. I use it for moderately complex as well as dumb I-just-want-a-few-variables-to-stay-updated things, the only downside being multisecond compilation times with many pages.