Oxford University Press is more than just a source for books. The prestigious publishing house also offers a wealth of resources for English language teachers worldwide. Many of the resources are free (or free to people who have already purchased Oxford publications) and many are non-print.
You can have Oxford content delivered to your RSS reader. Oxford lets you filter blog content so you get posts only in categories that interest you. The list of specific feed options is long:
Business & English for Specific Purposes
Dictionaries & Reference
Exams & Testing
Grammar & Vocabulary
Multimedia & Digital
OUP ELT News
Oxford’s English language teachers’ site is probably not the place to go if you are looking for a resource 10 minutes before class. To dig out useful free resources will take a bit of time. I suggest you look for resources when you are setting your course objectives for the year so you have an idea of what is available. Then use your RSS reader to monitor useful material that pops up over the course of the year.
[edited 2/26/2014 to remove links to material that has been moved behind a registration wall]