International Obfuscated C Code Contest – 2018 Winning Entries
Fabrice Bellard (the wizard behind FFmpeg, QEMU, etc.) has his own entry, which I find amazing: a ~4 kB program that outputs a ~50 kB image (of Lena), in addition to being able to decompress other images. His entry's hint page: http://www.ioccc.org/2018/bellard/hint.html