You may want to take a look at the Uzbl browser.
It's a minimalist web browser based on webkit (the layout engine used by Chrome/Chromium). According to the definition, it's a collection of "web interface tools which adhere to the unix philosophy".
It comes in 3 flavors:
The latter 2 are finished products and probably won't do what you're looking for. However the first one (
uzbl-core) is a nice wrapper around webkit and should fit the case you described.