My bad if this has been done recently but what are your favorite ir more memorable quests in Skyrim that either left a lasting impression or were just fun as hell to play through?

Off the top:

Walking Nightmare

Forsworn Conspiracy / No One Escapes Ciddha Mines

A Night To Remember

House Of Horrors

Pieces Of The Past

Thieves Guild minus the whole bit

The Dark Brotherhood

My favorite quest, hands down is the one where you sneak into the East Empire Company for the Thieves Guild. That was fun.

Another good one was sneaking onto the Emperor's galley and assassinating him.

Or the new Dawnguard quest exploring the Dwemer ruins to find aetherium.

Waking Nightmare
Mind of Madness
A Night To Remember (though I still haven't been directed to the hagraven...)
Diplomatic Immunity
Season Unending
Book of Love
Dungeons where you stumble upon quests: Forelhost, Valthume, Ansilvund, Ironbind Barrow, Frostflow Lighthouse to mention a few
...those spring to mind right now.

Blood On The Ice could have been great without the bugs.

I enjoy some of the misc quests as well. Delivering a potion from Bothela to the steward of Markarth always makes me giggle because he pays so good for my discretion Handing out pamphlets on behalf of the Temple of Mara was amusing - I felt like a Jehovah's Witness

I can think of more but gotta go. Screaming kids.

Nobody escapes Cydna mine.
Blood on the Ice.
Skooma Trade.
Dawnguard.
Recruit Gunmat and Sorine. (Dawnguard)
There are so many more those are just a few.

I also like those little miscellaneous quests found in random caves, dungeons and ruins. It's fun unkowningly stumbling upon something like what takes place in Ansilvund. I know they're mostly just short small quests but I really enjoy them.