Nicola Paolucci gave a presentation on powerful Git techniques including git worktree for working on multiple branches concurrently, git subtree for managing external dependencies, and git --fixup for cleaning commit history. Git worktree allows creating additional working copies of a repository for parallel work. Git subtree can integrate external projects cleanly and efficiently. Git --fixup helps squash raw commits before publishing branches. The talk demonstrated these techniques and emphasized their usefulness for collaboration and productivity.