For finance: 1) https://quant.stackexchange.com/ https://quant.stackexchange.com/ forum is worth following 2) https://quantocracy.com/ https://quantocracy.com

For finance: 1) https://quant.stackexchange.com/ https://quant.stackexchange.com/ forum is worth following 2) https://quantocracy.com/ https://quantocracy.com/ for article aggregators but no support for comments