Insert one character only
From Vim Tips Wiki
created April 30, 2003 · complexity basic · author johnmaxa · version 5.7
I have not yet seen this idea yet. But early in my use and love of Vim, I got frustrated in command mode when I wanted to insert just one character of text. So I put this in my vimrc:
"insert one character noremap <somekey> i<Space><Esc>r
I think it has been one of the most time saving mappings -- and I have remapped most of my keyboard.
This won't be repeated by the . command.
Therefore I define
nnoremap <somekey> :exec "normal i".nr2char(getchar())."\e"<CR> nnoremap <someother> :exec "normal a".nr2char(getchar())."\e"<CR>