From the text and comments at this link. I'm not recommending the books (most of which I haven't read), but I always enjoy posts about "best first lines" "best closing lines" etc in literature. For brevity, just the first lines are here - sources at the link for those interested.
"Physicist Leonardo Vetra smelled burning flesh, and he knew it was his own."
"They set a slamhound on Turner's trail in New Delhi, slotted it to his pheromones and the color of his hair."
"The five small craft passed from shadow, emerging with the suddenness of coins thrown into sunlight."
"In the summer of his twelfth year — the summer the stars began to fall from the sky — the boy Isaac discovered that he could tell East from West with his eyes closed."
"Brother Francis Gerard of Utah might never have discovered the blessed documents, had it not been for the pilgrim with girded loins who appeared during that young novice's Lenten fast in the desert."
"No one would have believed in the last years of the nineteenth century that this world was being watched keenly and closely by intelligences greater than man's and yet as mortal as his own; that as men busied themselves about their various concerns they were scrutinised and studied, perhaps almost as narrowly as a man with a microscope might scrutinise the transient creatures that swarm and multiply in a drop of water."
"Gully Foyle is my name
And Terra is my nation
Deep space is my dwelling place
And death's my destination."
"Once upon a time there was a Martian named Micheal Valentine Smith."
"In the week before their departure to Arrakis, when all the final scurrying about had reached a nearly unbearable frenzy, an old crone came to visit the mother of the boy, Paul."
"Far out in the uncharted backwaters of the unfashionable end of the western spiral arm of the Galaxy lies a small unregarded yellow sun."