A) Photography

Here you find a small selection of books on photography that I can highly recommend:

The Digital Photography Book: Part 1 (2nd Edition)

By Scott Kelby

Tony Northrup's DSLR Book: How to Create Stunning Digital Photography

By Tony Northrup

The BetterPhoto Guide to Digital Photography (BetterPhoto Series)

By Jim Miotke

Understanding Exposure, 3rd Edition: How to Shoot Great Photographs with Any Camera

By Bryan Peterson

Photography Q&A: Real Questions. Real Answers. (Voices That Matter)

By Zack Arias

The Adobe Photoshop Lightroom 5 Book for Digital Photographers (Voices That Matter)

By Scott Kelby

B) Hiking

There is an abundance of books on hiking! Here just a few for inspiration:

Mountaineering: Freedom of the Hills, 8th Edition

By The Mountaineers

Ultralight Backpackin' Tips: 153 Amazing & Inexpensive Tips for Extremely Lightweight Camping

By Mike Clelland

Lonely Planet Trekking in the Patagonian Andes (Travel Guide)

By Lonely Planet, Carolyn McCarthy

Lonely Planet Trekking in the Nepal Himalaya (Travel Guide)

By Lonely Planet, Bradley Mayhew, Joe Bindloss

Into the Wild

By Jon Krakauer

In Patagonia (Penguin Classics)

By Bruce Chatwin

C Running

If you read the following books then you should be highly motivated for trail and mountain running:

Beyond Training: Mastering Endurance, Health & Life

By Ben Greenfield

The Science of Running: How to find your limit and train to maximize your performance

By Steve Magness

Relentless Forward Progress: A Guide to Running Ultramarathons

By Bryon Powell

The Summit Seeker

By Vanessa Runs

Born to Run: A Hidden Tribe, Superathletes, and the Greatest Race the World Has Never Seen

By Christopher McDougall

Das große Laufbuch

By Herbert Steffny

D) Psychology

Some "must"-reads on psychology:

Anxiety: Using Depth Psychology to Find a Balance in Your Life

By Fritz Riemann

Forming Winning Strategies: An Integrated Theory of Habitual Domains

By Po L. Yu

Die Zweierbeziehung.

By Jürg Willi

The Crowd: A Study of the Popular Mind

By Gustave Le Bon

To Have or To Be? (Bloomsbury Revelations)

By Erich Fromm

The Art of Loving

By Erich Fromm

E) Finance

Here you see that I like the topics "Candlestick Charting" and "Behavorial Finance":

Psychology of the Stock Market

By G. C. Selden

A Random Walk Down Wall Street: The Time-Tested Strategy for Successful Investing (Tenth Edition)

By Burton G. Malkiel

Mastering the Trade, Second Edition: Proven Techniques for Profiting from Intraday and Swing Trading Setups

By John F. Carter

The Emotionally Intelligent Investor: How self-awareness, empathy and intuition drive performance

By Ravee Mehta

Japanese Candlestick Charting Techniques, Second Edition

By Steve Nison

Technical Analysis of the Financial Markets: A Comprehensive Guide to Trading Methods and Applications (New York Institute of Finance)

By John J. Murphy