Burning Down - very cool addition. Just to reiterate, because it can't be said enough - Bach
IS the master of fugue.
I hadn't heard the one you posted before, but my favorite fugue hands down has to be BWV 578 - "little fugue" in G minor.
J.S. Bach - BWV 578 - Fuga g-moll / G minor - YouTube
Again, Bach's a master in polyphonic music.
I wanted to append your voices discussion. Just because you found a fugue with 5 voices, doesn't mean you're limited to that :P. You could probably have a 50 - voice fugue, where each voice of a symphonic orchestra has a part (even the percussionist on a marimba!) Granted, you'd have a lot of muddied sounds, what with all the plethora of musical voices, but it'd still work and be fugal, don't you think?
That being said, 3-5 are totally common. 2's a little thin, and anything heavier than 5 is probably too chaotic to function in a pleasant way.
But oh, the possibilities.