Anytime I need help, on any video game, I always check this place first. Not only does it have info, but also leads to Strategy Guides created by fans on-line for when you need in-depth help. Simply could not have won Half-Life 2 without it.
I know it's something you could do in your head if you put the effort in - but it helps to be able to get the answer to Percentages more quickly - like to see how much you'd save with 20% off.
This is a great place whenever you have the need to translate some text from a foreign site. It only does up to 500 words - but that can be very helpful when searching blind through an untranslated site.
This is invaluable when buying anything in a foreign currency. I in particular use it to figure out how much I'm paying for something in Yen when buying stuff from Japan.
I've been very curious about learning Japanese, but don't have the money right now to take a class. This might not necessarily teach you the language, but I found it as a nice place to see what I'm potentially getting myself into. It also shows how to write Japanese characters, which I think is great, as I've never seen information on how to learn how to do it.
I actually use this site more to check when my spelling is bad. But it's also good for getting definitions for words and such.
I use this place whenever I need to find out the schedule for movies at the theater.