"BadWolf is a minimalist and privacy-oriented WebKitGTK+ browser.

Privacy-oriented
No browser-level tracking, multiple ephemeral isolated sessions per new unrelated tabs, JavaScript off by default
Minimalist
Small codebase (~1 500 LoC), reuses existing components when available or makes them available
Customizable
WebKitGTK native extensions, Interface customizable through CSS
Powerful & Usable
Stable User-Interface; The common shortcuts are available, no vi-modal edition or single-key shortcuts are used
No annoyances
Dialogs are only used when required (save file, print, …), javascript popups open in a background tab"

Seems surprisingly mature for its young (4ish years?) age.