Delete all local branches but master and the current one

git branch | grep -v "master" | grep -v ^* | xargs git branch -D;

what did I do? aka git last commit

git diff @~..@

What did I do the last week?

git log --stat --since='1 Week Ago' --graph --pretty=oneline --abbrev-commit --date=relative

git log only the relevant merges

git log --all --graph --decorate --oneline --simplify-by-decoration

show all untracked files

git ls-files --others --exclude-standard

last tag

describe --tags --abbrev=0