百度先森
[băi dù xiān sēn]
This nickname is a playful way to call someone as 'Baidu Mr.' 'Xianshen'(Mr.) sounds like a respectful address, however here it seems to have some joking meaning. 'Baidu' usually represents the well-known Chinese search engine; together, this username could be referring to someone who appears authoritative on matters searchable on Baidu.