'f' puts the contents of your previous cursor movement into the
find buffer. If that movement was a forward movement, it brings
the cursor back where it was. This allows for an efficient
combination of movements and 'E'. For example, if you want to
delete the next word, you type 'w', then 'f', then check your
"F" buffer to be sure, then press 'E'.

'X' deletes "modifier" characters following cursor.

'R' goes into replace mode at current cursor position.
Following keystrokes replace current character and advance
cursor. Press return to return to normal mode.