Polymathy is utterly unattainable in this age, with the breadth and depth of all human knowledge having blossomed. This is not to say: one ought not try. A Jack-of-all-trades may be a master of none, but is ofttimes better than master of one.
A community, then, for those who wish to have a broader base than is normal amongst scholars.
For myself, I claim some expertise in computer science at all levels (from hardware to software, from OS and language development to large systems engineering, from low level 3D graphics to MMPORPGs); electronics; electrical systems; physics including QFT, GR, solar physics, futurism; clock and watch-making; some mechanical engineering; philosophy; politics; and an interest in creative writing, poetry, art and music; and I love sports despite physical disabilities. Admittedly, I’m a bit blind on literature, chemistry and biology, but there you are.