surround: https://github.com/tpope/vim-surround
repeat: http://www.vim.org/scripts/script.php?script_id=2136
git: https://github.com/tpope/vim-fugitive (tim pope plugin)
undo: https://github.com/sjl/gundo.vim
for repls: https://github.com/jpalardy/vim-slime
for html: http://emmet.io/
EDIT: it looks like I use nerdtree at work.
:-)