As part of my last performance review, I negotiated an allowance for books with my boss. I have a set budget that I can spend on non-fiction books each month. In some ways, this is the best perk I have ever negotiated. You see, I really, really care about books and love reading. So every time I go and buy books at the beginning of the month, I feel happy about it. It makes me feel valued like almost no other thing I have ever negotiated for does.
Then, as the books show up over the course of the month, I am reminded again and again. It's like getting wonderful gifts all the time.
Having a set budget to spend on books and actually spending it regularly has significantly increased the amount of books I read. The topics are also more varied than before. I usually only bought books a couple of times a year and when I did, I tended to stick to the ones I wanted most and was most likely to read soon. I do not restrict myself in the same way now because well, the money is for books and books only. I never have to decide "Do I buy books, something else, or save the money". Books are the only option.
The variety of books has increased because I buy whatever interests me in the moment I buy the books. Sometimes there is a clear theme going on, sometimes less so. The fact that the books then lie around everywhere in my house eventually means that I pick them up and read them. Not all of them. Not in order, either. But more of them than I would read if I had to buy them first when "the mood strikes me".
A nice side effect: Whenever I go into a book store now, I don't have urgent cravings. Instead, I can focus on picking up specialty items. Things I really want and would not get anywhere else. I buy curiosities. Strange collections. Books that are beautiful in some way. Poetry. Zines. Things that make my heart skip a beat for a different reason than "oh, that's information that might be interesting".