I'm using MODPLUG composer (free) and MAGIX Music Maker (cheap). Modeplug is a list-oriented tracker that is based on instrument samples that are pitch-tranposed, where Magix is using a drag-n-drop timeline for samples, mainly loops, eg. 4/4 beats snippets.
Both are good for pop and rock sounds, pretty useless for classical music.
Acid Music 3, though I'm still a noob at it. Since Sony seems to have gone a bit insane lately ("No rootkit for me, thanks, I'm trying to cut down" <g>), I'm glad to have access to the pre-psycho-Sony version originally from Sonic Foundry.
Fruity is a good all rounder all-in-one package and I remember there's a good range of prices to suit all pockets - as they say. I never got on with its sequencer though.
I prefer 'Reason' controlled by a good sequencer like Sonar.