How do I align the viewport view so it is looking out of a selected object? How do I move an object to the viewport's view? This would be useful for placing some objects like lights where the viewport "camera" is, or aligning one object to another.
Viewport to object
To align the viewport to the object, select your desired object and hit CtrlNumpad0. This sets the selected object as the active viewport camera. Hit Numpad0 to return to your normal view, and return back to the object view again with the same key. Repeat this procedure on the camera when you are done in order to use the camera as normal.
Object to viewport
To align the object to the viewport, first set the desired object as your active camera and return to your view (steps above), then hit CtrlAltNumpad0 to snap the object set as your active camera to your current viewport view. You can also fly the view with ShiftF to move the object around with the view. You may need to enter wireframe mode by hitting Z (while not in fly mode) in order to see.
This is the same process you may already be familiar with when aligning the camera, but it also works on other objects.