Indy's whip is usually his main weapon along with his revolver. He uses it to swing across pits, climb up steep cliffs, or attack his enemies.
In the LEGO Indiana Jones sets, the LEGO Indiana Jones minifigure comes with Indy's whip. In the LEGO version, Indy's whip stays curled up.
In Lego Indiana Jones: The Original Adventures, Indy can use his whip to swing, attack, or grab objects.
In DS version of LEGO Indiana Jones: The Original Adventures, Thuggee Slave Driver also have whip. Same thing goes to Fedora in LEGO Indiana Jones 2: The Adventures Continue