isnt every key/button on the keyboard for creativity. Even if it has a specific purpose and use it exactly as so, u can still be creative with it. And if ur talking about "out of the box" situations, same thing applies. U can use anything "out of the box" if u can think "out of the box". A good portion of what we take as normal was "out of the box" at some point in time.
Most string instruments (guitar, bass, etc) have a natural ability to pitch bend, so when playing these instruments on the keys, u can use the pitch bend to simulate that effect. Now how/when u use it is all creativity now. But add the fact that this feature is still available when dialed in to instruments that cant normally do this opens a whole new world of "out there" kind of stuff. Some things are in bad taste or dont sound right, other things work. But its all up to you to make that call of which one it is.
Using pitch bend when playing synths or pad sounds tends to work pretty well.