Here are the resources I use most:
1. The online OED. Almost every day: for research, teaching, and sheer pleasure. Definitely more convenient than the hardcopy form, and, of course, more up to date.
2. Google Books. It has been a great way to get things like old EETS editions that I'm too lazy to take out of the library, or to chase down obscure footnotes in obscure publications that I don't want to trouble the interlibrary loans people about.
3. The Auchinleck MS online. Mostly for teaching; a lovely resource. The availability of good-quality MS facsimiles online has made a huge difference to my teaching, especially when I am located in the Canadian West, where medieval MSS are sparse. Hats off to the NLS for its generosity in sharing this important MS with the rest of us, and to Alison Wiggins and the late David Burnley for a beautiful edition.
Yin Liu
So, out of scholarly curiosity, what is your favorite digital/electronic/online resource (or type of resource), and why?
Dot