尘埃里的一粒沙
[chén āi lĭ de yī lì shā]
'尘埃里的一粒沙' (Chén āi lǐ de yīlì shā) literally means 'a grain of sand in the dust'. Dust already indicates trivialness, and among it is just a single particle of sand. Thus, this netizen name represents someone very humble and self-deprecating, possibly considering himself insignificant in a larger scheme.