For a Delta 3D printer I am designing I created these modules for OpenSCAD for quickly creating triangles. Thought I upload it encase anyone else wants to use them.

Modules for:-
Triangle,
Isosceles_Triangle,
Right_Angled_Triangle,
Wedge,
Equilateral_Triangle, and
Trapezoid.

Updated 8th Jan 2014 - Added support for different heights at each point of the triangle. This allows creation of wedges.
Updated 9th Jan 2014 - Trapezoid now just a single polyhedron

Add this file to you OpenSCAD working directory and add the following line to you OpenSCAD files you want to use these modules in:-
use