This thread drastically needs bumping, and drastically needs the Jpop taken out as that's really another thread in itself.
Massive kpop / khiphop fan here. It's not just the sound of the music, it's the whole image and attitude of the celebrities that I also find appealing. There is also the excitement of waiting for the new music videos to come out and seeing the awesome dance moves!

The whole Hanryu wave is interesting in itself. I watch a lot of Korean TV where you really get to see celebrities a great deal, looking into their personal lives as well as seeing them doing "normal" things, it shows they are really down to earth and normal people. It makes them seem a lot more accessible and I think that is appealing. For example the TV show Running Man where you get to see the celebrities really "winding down" for the show and just acting their normal selves and having a good time, including seeing SNSD bare-faced and in cute Pajamas, or the main girl of the show Song Ji Hyo, a massive drama star, she is incredibly down to earth and seems like a really nice person.
Besides, if North Koreans are willing to risk their lives by importing South Korean dramas to sell on CDs, DVDs and USB Sticks in the DPRK then it must be good! lol
Anyway I'll post a variety of stuff so there is something for everyone! I'll try to post stuff that hasn't already posted although a lot of good stuff has been posted so far!
CN Blue - Rock Pop. Everything CN Blue does sounds good, Jung Yong Hwa has a great voice.
A little different to their normal sound but I love this!
More Jung Yong Hwa, this time from the Neon Naega Banhaesseo (Heartstrings / You've fallen for me) OST.
And the title track from the OST
Anyway moving away from Jung Yong Hwa, here's some of the "usual" happy addictive kpop.
T-ara
f(x)
SNSD / So Nyeo Si Dae / Girls Generation. One from their new album that I thought was cute. Totally loving this at the moment, sounds quite christmasy too.
After School
Wonder Girls
Kara, omg I love Kara. Especially Kang Ji Young.
Kara was just as good even before Kang Ji Young and Goo Ha Ra were introduced. Totally love this one.
Kara's most recent hit.
The almighty 2NE1. My favourite song and one that wasn't posted further up. Incredible vocals.
BoA - Totally love this track, just sounds so fresh and summery.
Now moving out of the main pop and into stuff that is a bit less "pop" sound but still popular (That made more sense in my head). 4Men are an awesome quintet.
Kim Jong Kook, I am a massive fan of this. His voice is really different but it sounds really nice. Dare I say his voice sounds kind of like Michael Jackson's? :O
More Kim Jong Kook
And more
2AM (Not to be confused with 2PM). Still under the JYPE label but 2AM is like the ballad version. One of the members was actually posted above (Jo Kwon) because of terrible English haha. He's definitely one of the most flamboyantly straight men I've ever seen.
There is a huge amount more kpop, including all the boy groups like SHINee and Super Junior but there's not enough room for everyone so I suggest go searching around for their stuff if you're interested.
And now for khip hop. Starting with the classics of the 90s with Deux.
More Deux
Turbo. Remember Kim Jong Kook I mentioned further up? This is the duo he was in where he made his mark. Firstly a love one because I think they were awesome live and the dancing was just awesome. Kim Jong Kook is the one in yellow.
More Turbo, although this one is a bit more pop.
Now moving out of the hip hop pop style into the proper sounding stuff. I guess the main ones for me are Drunken Tiger and LeeSsang and more recently Tablo.
Let's start with Drunken Tiger.
More Drunken Tiger
And more

This one bumps HARD.
And... more! Another track that bumps hard.
LeeSsang
More LeeSsang
And more!
And more again!
And to finish off this truely long post, here is some Tablo.
And theeeen
And theeen
Hope this post will help at least one person discover more kpop!