Hey folks, has anyone come up with any good ways to make or download decent-sounding MIDI drum solos and drum fill-type material? I'm working on a demo tune on which I need a cool drum solo type outro where the drummer just goes nuts, but I can't find any midi stuff for that online.

I usually tap it out with my fingers on a desk, and then spend a long time programming it with a mouse.
If you play an instrument, you could also record the rhythm and then use Melodyne to change it to MIDI.  Then you just need to assign the notes to the right pieces on a drum map.

Hey! - I'm a drummer (acoustic and electric) but I also program drum parts.... I like to keep them (mostly) authentic  - i.e. most drummers only have 2 arms and 3 legs :) - but I like to program funky / complex stuff that I know I couldn't play.
Some of my stuff is here:
https://soundcloud.com/user-795249686
 
If you can let me have a demo track I'd be happy to have a listen and see if I can come up with some drum ideas for you??
I also use Cakewalk x3, so if you let me know what drum plugin(s) you're using, I should be able to program something compatible.......
 
Let me know if you're interested....

Jamstix, might be your best bet. It's not the easiest to use, but it is easier than manual programming.

For solos/fills I take a midi drum loop that has the feel I'm going for, switch hats/rides to toms and play around with it until it makes sense as a drum solo/fill. This usually works well as most pop/rock drum solos/fills are still connected to the groove in some way. Prog rock/jazz type stuff less so but there's a groove in there somewhere too . Hihat foot pedal hits are your timekeeping friends here too if you're going especially crazy on the other articulations.