The American Mathematical Society have created a system of online listings for people offering awards, fellowships, professional opportunities and other maths-related callouts. There’s a website at ams.org/
The system is aimed at mathematics faculty/scientists, institutions, programs, postdocs/early-career mathematicians, postgrads, undergrads, high school students and teachers (so, pretty much anyone involved in maths), and we’ve cheekily used it to post a call for submissions of articles for our Irregulars column, where we feature guest posts from other authors.
More information
Awards, Fellowships and other opportunities, at the AMS website.