Depeche Mode - I've listened to them since I was 12. My uncle had a compilation album by them and I copied it onto tape. Later on I bought all their albums and almost all their singles, except the latest album which sounded seriously uninspired.
I love them because Martin Gore is a great songwriter and I am a sucker for good electronic sounds. In addition, Dave Gahan makes it easy for me to sing along since we're both baritone voices.