Well, I'll do the fifteen minutes rule, but I can't guarantee I'll think of fifteen books in that time. I'm not even sure there are fifteen books that have had a truly "profound" impact on me, and I want all killer, no filler in my list! I'll add hyperlinks and comments after the time is up.
"All Creatures Great and Small" by James Herriot. Made me want to be a vet for about six or seven years. I didn't stick with that plan, but the idea was what first sparked my interest in a career in or around biology.
"The Hitchhiker's Guide to the Galaxy" by Douglas Adams. I was "different" as an adolescent - different from my family, and different from my peers at high school. I think this book was the first one I ever read that made me feel like my interests and sense of humour might just be shared by someone else*.
"Pride and Prejudice" by Jane Austen. I soooooooooooo thought I was Elizabeth Bennett when I was thirteen! I have "Pride and Prejudice and Zombies" on order; it's currently being held up as it's in the same order as something that doesn't come out in paperback until September. Can't wait.
"Cannery Row" by John Steinbeck. I fell head over heels in love with this book, and must have read it about twenty times by now. I turn to it when I'm stressed or unhappy, and Steinbeck's wonderful characters never fail to comfort me. This was also my gateway into his other, more serious, works, which helped shape my politics as I grew up.
That was eight minutes' worth and I'm now drawing blanks...
Oh! "Pecked to Death by Ducks" by Tim Cahill. A collection of adventure travel articles that first inspired me to try ocean kayaking. I will be forever grateful to Tim Cahill for this introduction to one of my favourite activities. I've read his other collections too, and they're all great.
Which reminds me... "Swallows and Amazons" by Arthur Ransome. Made me long for adventure; unfortunately, my one attempt at learning to sail resulted in a lot of unplanned ocean swims.
"The Chrysalids" by John Wyndham. One of my first forays into science fiction.
"Eva" by Peter Dickinson. Fuelled my passion for primates and the environment.
Well, that's eight (or twelve, if you count Hitchhiker as a trilogy of five books) - I did better than I thought I would! I'm sure I'll start thinking of more examples once I've posted this.
I tag... anyone who's ever fallen out of a sailboat.
*In his wonderful foreword to The Salmon of Doubt, Stephen Fry wrote the following:
“When you […] read Douglas Adams […], you feel you are perhaps the only person in the world who really gets them. Just about everyone else admires them, of course, but no one really connects with them in the way you do. […] It’s like falling in love. When an especially peachy Adams turn of phrase or epithet enters the eye and penetrates the brain you want to tap the shoulder of the nearest stranger and share it. The stranger might laugh and seem to enjoy the writing, but you hug to yourself the thought that they didn’t quite understand its force and quality the way you do – just as your friends (thank heavens) don’t also fall in love with the person you are going on and on about to them”.
Yeah. Been there, done that – although not with complete strangers! I would read snippets out loud to whichever friend or relative was nearest, but they never seemed to properly appreciate the words.