An incredible amount of similar content is available now in video and text form for free, but I think that the same ideas non-book form wouldn't have had the same impact on me.
Getting one or two book I love every month fills me with both joy and knowledge.
Most people in the publishing industry don't realise that I probably wouldn't have got into the industry or wouldn't have reached my current level without some pirated books.
I can now afford without many problems to spend 60+ euros on a book and I'm doing it. Not often, but I'm doing it (books take time to read :) ).
My last purchase was advanced programming in the Unix environment (~65 euros), about one month ago, I'm currently at about page 200 out of ~970.
O'Reilly is going to get so much money from me in the next years... They kinda deserve them lol.
Programming:
* Analyzing Computer System Performance with Perl::PDQ - Gunther
* The Mythical Man Month - Brooks
Philosophy:
* A Journey Around my Room - de Maistre
* Anger, Mercy, and Revenge - Seneca
* Schrödinger - What is Life?
* Man's Search for Meaning - Frankl
* Essays - Montaigne
* Ethical Intuitionism - Huemer
* The Consolations of Philosophy - de Botton
* A Manual for Living - Epictetus
* Meditations - Aurelius
Psychology / Meaning / Purpose / Science:
* Purpose and Meaning in the Workplace - Dik, Byrne & Steger
* The Case Against Education - Caplan
* Selfish Reasons to Have More Kids - Caplan
* Dawkins - The Selfish Gene
* A Confession - Tolstoy
* Enlightenment Now - Pinker
* The Better Angels of our Nature - Pinker
* The Improving State of the World - Goklany
* The Skeptical Environmentalist - Lomborg
* Religion for Atheists - de Botton
* Ending Aging - de Grey
* Gut Feelings - Gigirenzer
Fiction:
* Heart of Darkness - Conrad
* Candide - Voltaire
* Brave New World - Huxley
* Selected Works - Goethe
* 1984 & Animal Farm - Orwell
Politics:
* Obedience to Authority - Milgram
* The Problem of Political Authority - Huemer
* The Communist Manifesto - Marx
* Socialism - von Mises
* Just One Child - Greenhalgh
* The God That Failed - Crossman
* Death by Government - Rummel
Thought-provoking:
* Free to Learn - Gray
* The Beautiful Tree - Tooley
* Education and the State - West
* The Machinery of Freedom - Friedman
* Against Intellectual Monopoly - Boldrine & Levine
* From Mutual Aid to the Welfare State - Beito
* The Not So Wild, Wild West - Hill
* More Guns, Less Crime - Lott
* Race & Economics - Williams
* Emancipating Slaves, Enslaving Free Men - Hummel