I used to listen to a ton of electronica when I was in college. Not so much now. Just very occasionally.
Back then my favorite genres were Trance, Hard House, and some Ambient.
Some artists I liked were Orbital, Sasha and John Digweed, DJ Micro, DJ Irene, Underworld, Paul Oakenfold, Sash, and The Orb, among others.
Nowadays I don't listen to music much. Mainly only while driving. It's a shame bc I used to listen to my iPod for 2-3 hours each day. I'd also listen to my music on iTunes while online. Music is just one more interest that's fallen by the wayside over the years. It seems boring now for the most part.
If I do listen to music now, it's usually Alternative.
At one point or another, I liked Rock, 80's (especially new wave), 90's Alternative, some Hip Hop, Classical, Gregorian Chant, Industrial, 70's Rock, and Disco, among others. Pretty much everything except Country, Bluegrass, Jazz, and hardcore Rap.
As for Happy Hardcore, I HATE that shit with a passion. It is the most annoying genre of music that I know. KandE kids tricked out in bright, garish colors; bopping around, high on E, stimulants, and sugar; blowing people up; hugging each other; and peddling candy and PLUR like it's going out of style. So. So. So. Annoying.