My complete .gitconfig file that I take everywhere I go. I included comments for all my aliases that aren't obvious.

.gitconfig

[user]
	name = J.D. Mallen
	email =
	# uncomment the below to add a GPG signing key
	#signingkey =
[core]
	askpass = git-gui--askpass
	autocrlf = true
	editor = vim
	pager = less -x1,3
[commit]
	# uncomment the below to sign all commits by default
	#gpgsign = true
[push]
	default = simple
[alias]
	# adds all files, including untracked, to the working tree
	a = add
	aa = add -A .
	
	# adds files while disregarding whitespace changes (handy when line endings 
	# get changed)
	addnw = "!sh -c 'git diff -w --no-color \"$@\" | git apply --cache --ignore-whitespace' -"
	
	# alias inception-- an alias to create a new alias. usage printed with cmd.
	alias = "!sh -c '[ $# = 2 ] && git config --global alias.\"$1\" \"$2\" && exit 0 || echo \"usage: git alias <new alias> <original command>\" >&2 && exit 1' -"
	
	# applies a git command to all subdirectories that are git repos
	# e.g. assume you have ~/projects/repo1, ~/projects/repo2, you can run 
	# `git all fetch` in ~/projects to run `git fetch on repo1 and repo2
	all = "!f() { ls | xargs -I{} git -C {} $1; }; f"
	
	# add patch-- stage just parts of files
	ap = add -p
	
	# deletes uplinks to remote branches that have been deleted
	# and deletes local branches that have been merged other than
	# master and your current checked out branch
	bc = "!sh -c 'git fetch -p; for b in $(git branch --merged | grep -v \"*\" | grep -v master); do git branch -d $b; done'"
	
	br = branch
	branches = "!echo ' ------------------------------------------------------------' && git for-each-ref --sort='-authordate:iso8601' --format=' %(authordate:relative)%09%(refname:short)' refs/heads && echo ' ------------------------------------------------------------'"
	
	# automatically stage all modified files that are tracked (does not add new 
	# files) and commit with a message in quotes, 
	# e.g. `git ca "Fix bug in the place with the stuff"`
	ca = commit -am
	
	ci = commit
	cl = clone
	co = checkout
	cob = checkout -b
	
	# following unsuccessful merge, list files that have Unmerged changes; i.e.,
	# files with merge conflicts
	conflicts = diff --name-only --diff-filter=U
	
	cp = cherry-pick
	
	# commit GPG-signed
	cs = commit -S
	
	# get diff of staged files, excluding minified files
	dc = "!sh -c 'git diff --ignore-space-at-eol --cached $1 \":(exclude)*.min.js\" \":(exclude)*.min.css\"'"
	
	# get diff of unstaged files, excluding minified files
	df = "!sh -c 'git diff --ignore-space-at-eol $1  \":(exclude)*.min.js\" \":(exclude)*.min.css\"'"
	
	# possibly my favorite: if you accidentally type git twice, e.g. 
	# "git git push", the command you originally wanted will still work.
	# it cancels out subsequent "git"s
	git = !git
	
	# delete all changes made since the last commit. careful with this one!
	hard = reset --hard HEAD
	
	# extremely verbose git log. combination of `git show` for all commits, 
	# along with the diff between that commit and the one prior. best used with 
	# a specific commit hash, e.g. git lg 123abcd
	lg = log -p
	
	# list of commits, one line a piece. very easy to fetch a specific hash
	lp = log --oneline
	
	mg = merge
	
	# force a recursive merge, no fast-forwarding
	mn = merge --no-ff
	
	pl = pull
	ps = push
	pushup = push --set-upstream origin 
	
	# ever try to push a branch for the first time and get that annoying message 
	# to --set-upstream? this does it for you.
	pu = ![[ $(git config "branch.$(git symbolic-ref --short HEAD).merge") = '' ]] && git push --set-upstream origin $(git symbolic-ref --short HEAD) || git push
	
	ra = remote add
	rd = remote remove
	re = remote
	rs = remote set-url
	
	# list all remotes
	rv = remote -v
	
	# the best way to see the status: each file on one line, and one line to 
	# show the relationship to remote branch
	st = status -sb
	
	# lists the contributers with how many commits each
	who = shortlog -s --
[http]
	sslVerify = true
	# uncomment the below to force git to use the Windows certificate store
	# (Windows only, obviously)
	#sslBackend = schannel

# The rest is so I can use Beyond Compare 4 for fancy diffs/merges. 
# Delete if you don't use it.
[diff]
	tool = bc
[difftool]
	prompt = false
	bc = trustExitCode
[merge]
	guitool = bc
	tool = bc
[mergetool]
	bc = trustExitCode
[difftool "bc"]
	path = c:/Program Files/Beyond Compare 4/bcomp.exe
[mergetool "bc"]
	path = c:/Program Files/Beyond Compare 4/bcomp.exe