<SHIFT><ALT> + left mouse: Box select
<CTRL> + d: Multi select. Add next instance of the word at the cursor
<CTRL> + u Multi select. Undoes last multi-select
<SHIFT><ALT> + left mouse button drag: Multi select up/down
<SHIFT><ALT> ++ left mouse click: Multi cursor wherever mouse is (free form)
<SHIFT><ALT> + Up arrow / down arrow: Copy current line above / below current line
<CTRL> + /: Comment / uncomment line <SHIFT><ALT> + a: Block Comment / uncomment line