X-JAPAN: THE Japanese rock band of the late-80's and 90's. Lead by Yoshiki (drums), other members were Toshi (vocals), Pata (guitar), Hide (guitar), and Heath (bass guitar). When they first broke on the scene there was a different guy on bass, but I don't remember his name.
Anyway, a lot of people have likened their style of music to Queen, in that they've done everything from hardcore rock, to symphonic rock, to some pretty kick-ass ballads.
Yoshiki, as leader, was also the principal songwriter, composer, and producer for the group (as well as many other JRock acts which he still works with). He's musically very daring and bold, willing to try new sounds in an attempt to continually evolve the sound of the music. He's also a major perfectionist, which may be part of the reason his newest/latest/current project, Violet UK (which has been "in the works" for at least 6 years), hasn't been able to really get off the ground.
Anyway, X-Japan had broken up sometime in '96 or '97, partially 'cuz the guys wanted to do solo projects, but largely due to tensions within the group reaching an all time high. Sometime in '98 (I think), the guys apparently mended some of their fences and had planned to reunite/re-form the band (everyone except Toshi was in). Tragically, this reunion never happened because Hide died (overdose, I think). They did have a psuedo-reunion when the remaining members got together at Hide's funeral and played some of their songs as a tribute to him. With Hide's death, X-Japan was dead.
So now, Yoshiki is still writing, producing, and on occasion playing drums with some other bands. I'm not sure if he's still working on Violet UK. As for the others, they've each released some solo works (saw them on EBay). Other than that, I'm sorry to say I don't know much about what they've been up to.
Hope that helps a bit. I'm sure I'm leaving out a ton of other stuff. If anyone else can add to this, feel free to do so.