Using arduino's 5v and 3.3v lines at the same time.

I have 2 components that I need to power with arduino uno. One of them needs 5v and the other 3.3v. Would it be possible for me to power each one separately using the arduino's 5v and 3.3v power pins and connecting them to both ground pins on the arduino without damaging them? Or would I need to do something else like use a voltage divider?

Yes to all. Mind the current draw.