So, the most recent three philosophy texts I've read are: Phenomonology of Spirit, Being and Time, and Naming and Necessity.
They have all blown my mind, and gone on my reread shelf for next year. What's another tome of philosophy that will fuck my mind?
If you're into phenomenology, Merleau-Ponty's The Visible and The Invisible is a must read. It is a manuscript published after his death, so it's in an unedited state and can get tedious to read at times, but the insight provided is incredible.
To add to this: if you're unfamiliar with Husserl you should read him first. Cartesian Meditations is a good place to start I think. Merleau-Ponty discusses Sartre's Being and Nothingness a lot, but you can get by without reading it since the text explains it before criticizing it.
Thirst for Annihilation - Nick Land