What are some effective techniques that can be used to change key in a composition?

Here is a list of some techiniques:

1) Using a secondary dominant to move to the dominant key

2)Augmented 6th

3)Diminished 7th - use one of the notes within the dominant 7th as a 'leading note' to a desired key

4)Cycle of 5ths

5)Semitone movements - usually within a less tonal piece