Recently, I very often visit to this board and sometimes receive a help by your reply. 

It is because here there are many people who are good at English. hahah

Anyway, i want to share my favorite helpful sites for English with you and also know what favorite sites you have.

I just share these sites as first. 

http://ted.com - i think you almost know this sites, a kind of speech site in English about diverse topics.

http://www.urbandictionary.com/ - When i search slang in English, I frequently use this site.  

If you have other sites, why don't you share those things with us? :)