Free: Tweakgit Com
TweakGit.com was a tiny web tool dreamed up by a couple of ex–open-source contributors who wanted a gentler way to teach Git. They launched a minimalist site with a single promise: “Play with commits — nothing scary.” The interface was paper-simple: a sandboxed repo, drag‑and‑drop commits, visual branching, and an undo button that never scolded you.