I always use carbonation drops/tabs. Its odd because I'm one of the most paranoid people you'll ever meet regarding contamination/sanitation, but all I do is bottle, wash my hands, immerse my fingers in sanitizer for a moment, and pick up the tabs with the tips of my fingers.
I've heard of people boiling some wort (made from DME), letting it cool a bit, putting it into a bottling bucket, siphoning the finished beer on top of it, and bottle from there. I see that as an opportunity to introduce a bunch of oxygen. I don't know yet which is worse, germs on my fingers or oxygen from the bucket.