If you haven't already done everything . I have still not properly expored the Reach, or made a home in Hjaalmarch. Nor have I ever done the Stones of Barenziah quest. Doubt I ever will xD

I have also never properly played a Redguard, Orc or Khajiit. They are three races I quite like, but have never played as. I've played as a Nord and Imperial the most, closely followed by Dunmer and Bretons, and I have a Bosmer inspired by the http://s1264.photobucket.com/user/crazyfoomandude/media/esobosmer.png.html I'm not a massive Argonian fan, so I doubt that I will ever make one. Perhaps some day.

I had a High Elf once. Meh.

Still have not done the Companions quest line, on any of my characters.

Still have not gotten married

• I've never finished the Main Quest. (I hope I'm not alone in that, I hear stories of others who never do the MQ but even so...)
• Never played a pure warrior character (That's true for all TES games actually, I'm always a Mage / Assassin.)
• Never played as a Redguard, Orc, Bosmer, Argonian, Khajiit or Imperial. Always Nord / Breton / Altmer / Dunmer.
• Never chosen to destroy the DB.
• I am plagued with restartitis so I've never got my Conjuration high enough to get Dead Thrall despite dabbling in Necromancer builds constantly.

I have tons more of these, which may or may not be a bad reflection on my playstyle considering I have hundreds of hours into Skyrim....

Never done the different variations of the Season Unending quest.

There are a couple of random encounters I haven't seen like Babette feeding on a road, and only one member of the roaming Dawnguard (I've seen the other twl)

And I've never (tried, but failed) discovered the 4 mountain peaks of Solstheim.

Other than that, I've seen it all and done it all.

I have yet to play the game as an argonian. I've created several but they never made it past anything at all really. Not sure why.

I have yet to collect ALL daedric artifacts.

I have never sided with the vampires in Dawnguard or played as a vampire lord.

Never collected all the Black Books for dragonborn.

I still haven't rebuilt the Thieves Guild nor done the associated side quest involving Linwe and never destroyed the Brotherhood. Aside from Cidhna Mine, I've never allowed myself to be arrested either.

ha I do that with nearly every character

I've been tempted to build a character who gets arrested in each hold just so I can break them out of jail. So far only broke myself out of Whiterun.

Some major things I haven't done are:
The Dragonborn main questline
The Dark Brotherhood questline
Collect all Daedric artifacts (and probably never will, at least not with one character)
Collect all Dragon priest masks with one character
Joined the Volkihar side in the Dawnguard questline
Killed Paarthurnax or done any of the Blades' dragon hunting quests
Killed Nazeem

Wow, I never even heard of the Babette one until now. Interesting...

When you say discover Solstheim's four peaks are they actual locations or just getting to the tops of mountains? (I've not done it, either way)

Never done the Civil War and never will.

Never killed Paarthy and never will.

Never sided with Stormcloaks

Never became a vampire

Have not visited Solstheim yet

Never build own Hearthifre house or adopted any child

Never played any other race than Dumer, Nord and Breton

Never mastered any magic skill

Never got piece of Daedric armor

Never killed Saadia

http://www.gamesas.com/topic/1430003-the-peaks-of-solstheim-location-spoilers/

http://elderscrolls.wikia.com/wiki/User_blog:TombRaiser/Dragonborn:_Hidden_Landmarks

I have not done this either, did not even know they were there to be found.