Here's a great article describing a useful Git tool called tig.
One thing it doesn't mention is that you can actually press comma (,) when doing a tig blame, to do a blame on the parent commit. This is useful if the blame on the current commit isn't showing who really changed the line. You can do blame on the line all the way up the parent tree.
Other tig tips:
- Use this to browse the tree of another branch: tig origin/rel-1.5.
- If while browsing the commits on another branch you press Shift+C on a commit, it will cherry-pick it into your current branch.