"Ozymandias" will always be in his voice in my mind. It's one of the few poems I'm at all familiar with, and I like it a lot.
edit: Here's the poem, below, for anyone interested. And for anyone unfamiliar with what my parent's comment means: In the game Civilization IV, researching a technology is accompanied by a quote. Nimoy reads these quotes aloud, in this game, and '"And on the pedestal these words appear: / 'My name is Ozymandias, king of kings: / Look on my works, ye Mighty, and despair!' / Nothing beside remains."' is the chosen quote for the "Construction" technology. You can probably find audio of it on the internet (which I recommend), but I can't youtube at work.
I met a traveller from an antique land
Who said: "Two vast and trunkless legs of stone
Stand in the desert. Near them, on the sand,
Half sunk, a shattered visage lies, whose frown,
And wrinkled lip, and sneer of cold command,
Tell that its sculptor well those passions read
Which yet survive, stamped on these lifeless things,
The hand that mocked them and the heart that fed:
And on the pedestal these words appear:
'My name is Ozymandias, king of kings:
Look on my works, ye Mighty, and despair!'
Nothing beside remains. Round the decay
Of that colossal wreck, boundless and bare
The lone and level sands stretch far away.
Unfortunately, my stupid sense of humor makes me remember his Sputnik the best of all those little quotes. Somewhere on YouTube there's a black screen with the audio looped for hours.