I like physical books, and I want to buy more. But for $1k you can also get access to O'Reilly's [0] library ($499/year) which has a ton of excellent books on a variety of topics (not just programming). It's not as good as 10 years ago when they offered download tokens (I have so many PDFs from those days), but it's still a good system. And you can sometimes get discounts (ACM or IEEE used to get you access for half the cost, so total of ACM/IEEE + O'Reilly was basically the same as just O'Reilly, not sure the current discounts I get it through my employer). Then that $500 remaining can be directed towards higher quality books (especially ones you want on your reference shelf) or other materials.