Off-topic, but useful key combinations for bash:

    C-r      search history and recall (C-R for another match)
    C-o      run and recall next (C-O next, C-O next, ...)
    C-M-/    undo last edit
    M-d      delete next word
    M-backsp delete prev word
    C-y      paste text deleted by the two above (combined), Emacs's "yank"

M means Meta key, substitute Alt key on a PC.

Not really off-topic, these combos facilitate writing fabulous one-liners.