The Sicilian Chekhover Variation is a chess opening named after its most famous practicioner Vitaly Chekhover. Although the Chekhover Variation is rarely played in grandmaster games, it is actually not uncommon among amateurs. On move four white ignores the standard opening advice to not move the queen out early in the game (as it may become a target in the center). The move order goes 1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Qxd4?!
Black's main response to the Chekhover Variation is the obvious looking 4...Nc6 attacking White's queen, however, there are many more to choose from.