And don't follow the way Oblivion made it: not any achievements/trophies for completing quests, or maybe special ones if you really want to
Here are a few I though about
Vengeance! - kill someone after he mentionned mudcrabs...
And I thought you were a god - Kill Alduin without getting hit
My old clothes still fit? - Boost your strenght to 100
The Eye of the Tiger - kill a minotaur without using any weapon but your bare hands
Robin Hood - Steal money from a noble, and give it to a beggar
Melting Ice - Freeze someone, then burn them
Time to Get Technical - kill an enemy who's at least 4 levels higher than you are
God I hate Reading! - Hit a book with your weapon, or cast an offensive spell at it
Watt? - Cast lightning continuously until your magicka runs out
I Command Thee To Open! - Open a door with a dragon shout
Yet again, this is just for fun, and in case someone wasn't following, THEY WON'T BE IN THE GAME
So what can you come up with?