Quickly add Tim Pope's ctags generation scripts to all Git-controlled directories under the current one, so that you don't need to recreate your repositories.

gistfile1.sh

# I love tpope's solution to ctags regeneration[1]; he creates
# a template from which all Git repositories take their default hooks,
# and then uses these hooks to regenerate ctags.
#
# [1]: http://tbaggery.com/2011/08/08/effortless-ctags-with-git.html
#
# It's an elegant solution, but what do you do about repositories that
# already exist? The template will only apply to newly cloned or newly
# initialised repositories.
#
# This one-liner should help; it will check for version-controlled
# directories one level below the current directory, and then copy the
# hooks over into them.

for x in *; do; [[ -d "$x/.git" ]] && echo $x && git init; done

# This won't actually generate the ctags; they'll be generated the next
# time one of the hooks is run (e.g. the next time you do a pull).
#
# If you'd like to regenerate them without waiting, you can use the
# following:

for x in *; do; [[ -e "$x/.git/hooks/ctags" ]] && echo $x && chdir $x && .git/hooks/ctags && cd ..; done

Amazing! Much simpler.

Updated.