I began playing with
Scream Tracker (DOS), followed by
Impulse Tracker (DOS, aka Fast Tracker 2), and then there was
ModPlug Tracker (WIN).
Then -in my life- came
Rebirth and the freeware program
Hammerhead (which is very good, check it out!). After that I switched to
Jeskola Buzz for a while, before I *stumbled upon*
Reason. Now it's reason all the way, baby

Not that I'm really good at it, but there's some potential and it's fun to use anyway.
I've tried some
Ableton Live as well, but that's still too confusing for me.