I really miss making music. Ironically, it was a lot easier when I had fewer choices. Now, I have a bona-fide MIDI keyboard with full-size keys, a professional editing suite, a kick-ass sample library or two, and some other stuff I've barely touched. (Not to mention the acoustic guitar, for that matter; I sold the electrics a month ago.)
So what's stopping me? Time, mostly, I guess. But I also find myself paralyzed by knowledge. I know a lot more about music theory than I used to in the days that I just slapped notes and chords together. For instance, I never knew what a "fugue" really was, so anytime I wrote something contrapuntal, I'd call it a "fugue." I also didn't know what you "needed" to do to introduce key changes, so I would just change keys as the whim struck me. And finally, I didn't know how to play the piano. That meant I just wrote stuff on staves and then had the computer play it out loud, and if I didn't like it, I'd make changes.
Now, I rely on Apple Loops in Soundtrack and GarageBand because they sound so much better than anything I could make myself, and they're a lot quicker. But I've lost the soul, and the joy, of composition in the process.