*** (3 stars out of 5)
Why not steal one? I mean, if you've already stolen a translocator (which, if you'll recall, is like a long-distance transporter that punches easily through shields and dices tin cans.) And if you've also stolen a starship's main computer and Portable Holo-emitter. After all, a bushy-bearded 15th century artist should be useful to your alien criminal empire! Why, just think of it! He could... um... AND he... well...
O.K., so I can't think of anything, either. But he makes a great conversation piece and he doesn't eat much at all!
Thankfully, Janeway instantly catches the crooks napping and snatches back her simulated hero (and, one would think far more importantly, the one-of-a-kind emitter). Still in character as da Vinci's apprentice, she drags the delightful but not very useful archaic genius along on her hunt for the main computer (without which, you'd think, Voyager wouldn't be up to any tricky maneuvers except falling out of the sky). Hampered by Leonardo's many pompous questions, the Captain does not avail herself of the easy option of putting him on "pause" and just pocketing the emitter. But, of course, there's no need for efficiency: the bad guys can't shoot straight anyway.
"Concerning Flight" makes reference to "Requiem For Methuselah" when Captain Janeway says Captain Kirk claimed to have met da Vinci. A neat trick, since Spock erased Kirk's memory of the whole thing. Which thankfully implies that Spock must have thought better of his action, and perhaps more thankfully, that jerk-bag Flint must have died or Kirk wouldn't have blabbed about it. Of course, it's also a little bit "The Savage Curtain" with our illustrious Captain getting to pal around with her historical idol the way Kirk did with Lincoln.
What weird hat will Gimli wear next? Gimli fires a phaser! Gimli rides in an Ewok hang glider! I'm not immune to John Rhys-Davies many charms. The man can elevate any material. He was in Sliders, after all.