ExportTable is a faster implementation of Mathematica's Export[..., "Table"] for matrices of real numbers.

The following example demonstrates the superior performance of this package versus the built-in method:

data = Table[{1. x, 1. y, 0.}, {x, 1000}, {y, 10^3}]~Flatten~1;

AbsoluteTiming@Export["test 1mio points.txt", data, "Table"]
(* Out: {23.9979, "test 1mio points.txt"} *)

<< ExportTable`
AbsoluteTiming@ExportTable["test 1mio points.txt", data]`
(* Out: {0.0381513, Null} *)

Inspiration for the package: http://mathematica.stackexchange.com/questions/120015/fast-way-to-export-large-amount-of-data-in-table-format