Some pretty cool stuffs:
(Joyful to read) Vitali Milman: Today I am 80!
(Game Theory) Spencer's Lemma (combinatorial equivalent of Brouwer Fixed-Point Theorem) and Kakutani Fixed-Point Theorem
(Event-Triggered Control) To sample like a Lebesgue integrator
(Fourier Transform) Visualization!
(Matrices) Old and New Matrix Algebra Useful for Statistics by Thomas Minka pdf!
(101 Optimization) Linear and Nonlinear Programming by David G. Luenberger and Yinyu Ye book!
Some of my drawings and a photo of my beautiful nieces :