SAE: http://lib.sinaapp.com/ 
Google: https://developers.google.com/speed/libraries/devguide?hl=zh-CN  
Baidu CDN :http://developer.baidu.com/wiki/index.php?title=docs/cplat/libs  
jQuery CDN :http://code.jquery.com/  
Bootstrap CDN：http://www.bootstrapcdn.com/  

CDNJS http://cdnjs.com/ 
jsdeliv http://www.jsdelivr.com/

MS :http://www.asp.net/ajaxlibrary/cdn.ashx