Keyboard:  CTRL + DEL (forward); CTRL + BACKSPACE (backward)
Command:  Edit.WordDeleteToEnd; Edit.WordDeleteToStart
Versions:  2008,2010
Published:  4/6/2010
Code:  vstipEdit0040

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This one is interesting.  You can delete from the current cursor position to the beginning or end of a word.  Let me Illustrate with a simple example.  Let's say you want to change this word:

Given the current cursor position you could press CTRL + DEL:

Then type the new word:

This is a somewhat contrived example but you get the idea.  Additionally, CTRL + BACKSPACE will delete to the beginning of a word.