One of the best online resources for graduate students, especially those aspiring to academic careers in research or teaching, has to be the Tomorrow’s Professor (TP) mailing list:
http://www.stanford.edu/dept/CTL/Tomprof/index.shtml
Managed by Rick Reis, a professor of engineering at Stanford, the list produces entries twice weekly on a wide variety of topics relevant to graduate students, postdocs, and faculty members, many of which are excerpted from recent journals or books.
I first learned about TP through a colleague who forwarded one of their e-mails regarding teaching. Since then I have been actively reading most of the postings, which I’ve found to be both an outstanding source of advice and a great way to keep abreast of the latest issues in higher education and education research.
Anyone can subscribe to the list to receive the regular e-mails (subscription instructions available on the above URL), although the website contains a full archive of previous posts. There is also a blog that regularly reposts the content: