I don't know what was happening yesterday, but my WiFi connection was insanely slow. Naturally, it had to happen when I was awaiting an important email, and my Gmail was taking so long to load.
Once again, Gmail to the rescue! You can now enable an Inbox Preview lab that will show you the first 10 emails in your inbox, before your entire Gmail account appears. This way, if you have a bad Internet connection like me, you'll be able to see if you have any new emails — without having to wait half an hour for the page to completely load.