Combine water and vinegar in a small bowl.
Combine flour and salt in another bowl.
Using a pastry cutter or your fingers, cut butter and cream cheese into flour mixture until mixture resembles coarse crumbs with some larger pieces remaining.
Add water/vinegar mix to dough in a slow, steady stream, stirring, until mixture just begins to hold together.
Turn out onto a piece of plastic wrap, and wrap. Press dough into a disk using a rolling pin.
Refrigerate until firm, about 1 hour or overnight. (Dough can be frozen for up to 1 month; thaw before using.)
Roll dough into a 12-inch round on a lightly floured surface.
Fit dough into a 9-inch pie dish. Trim edge, leaving a 1-inch overhang.
Turn overhang under so that edge is flush with rim. Flute edge.
Freeze until firm, about 15 minutes.
