Favorite Korean Drama OST?

Usually the OST for a drama is one of the biggest reasons I miss a drama when I complete it, because I get so attached to the music <3

Some of my favorites are City Hall and My Girlfriend is a Gumiho, because they both have really beautiful slow songs ("Anxious Love" and "Fox Rain" respectively).

What about you guys, what are your favorites? ^^

You're Beautiful
Dream High
I am Legend
Mary Stayed out All Night

And I agree with Hava for the My Girlfriend is a Gumiho

Dream High, You're Beautiful and Spring Waltz are my favorites. xP

i loved
never say goodbye by mario & nesty- from my girl
depression of the director(insttrumental)- from personal taste
some tracks from you're beautiful were also nice but i have not checked them out completely.... :)

Spring Waltz
My Girlfriend is A Gumiho
Soulmate
My Princess
Dream High
Invincible Lee Pyung Kang
Baby-Faced Beauty
Tamra the Island

OST. fav Korean Drama:
My Girlfriend is a Gumiho (Fox Rain) | Personal Taste
My Princess | Secret Garden
Lie to Me |Mary Stayed Out All Night
The Greatest Love |Soulmate
All about Eve |You're Beautiful
Hotelier |Winter Sonata
Full House |Goong

Here’s my top five - not in any particular order.

Witch Yoo Hee. The OST is perhaps better than the drama. I liked almost all the songs, the music is very energetic and I listened to it long time after I finished the show.
Coffee Prince. The OST is evenly great, not just one or two good songs. Makes you feel happy.
City Hall. Many, many great songs and I pretty much liked all the instrumentals as well.
Personal Taste. Many great songs I can still listen to every now and then. The only exception is 2AM’s “Like A Fool”. I got an overdose of it.
Secret Garden. A very good OST that suits the drama well, especially fell in love with “That Man”.

And a few songs/OSTs that I want to mention as well:

Dream High. The title song “Dream High” and Taecyeon’s “My Valentine” are great.
Oh My Lady! I liked SNSD’s "Sunny" and 4men’s song from this OST.
Full House. Especially Byul’s “I Think I love You”.

Top 4 favorites-

Winter Sonata
The soundtracks of this drama are incredibly beautiful; especially 'Cheoeumbuteo Jigeumkkaji' and 'My Memory' by Ryu and their instrumental versions. I had downloaded the OST a long time back before watching this drama because I had listened to 'Cheoeumbuteo Jigeumkkaji' on Youtube and fell in love with it. The OST was actually the reason why I decided to watch the drama. However after watching the 1st episode and the first few minutes of the 2nd episode, I had to drop it because I got bored and didn't feel like watching any further but perhaps I will watch it some day in the future if I don't find any other good drama to watch.

Goong
The traditional music is amazing, plus 'Perhaps Love' by HowL & J, 'Dan Shin Eun...' by Stay, 'Parrot' by HowL and 'Ice Pond'.

Full House
This is another drama that I haven't completed yet. I can't say I have dropped it. I watch it bit by bit when I am not feeling like watching any of the dramas that are on my 'currently watching' list. I love its OST. It is classic! The song 'Oon Myung' by Why and its instrumental version are very catchy; 'I think I love You' by Byul as well.

1 Litre of Tears
I am speechless. I can't say which ones among its soundtracks are the best. I love the entire OST of this drama. The main theme always makes me emotional whenever I listen to it.