Baidu is a hoodlum.

If you are in China (technically it's your IP address that's in China,) go to mp3.baidu.com and type any word you like. Pay attention to the number of results that you get.

Then try to get an IP address outside China. You may want to try some of those proxies such as www.secure-tunnel.com. Then go back to mp3.baidu.com with that non-Chinese IP address. Try search the same word you typed just now.

Notice some differences? Here are the reasons.

死猪不怕开水烫？现在去baidu又可以搜到mp3了。