Great! New resource for problems. I bought an SAT math only workbook, and it's chock chock CHOCK full of geometry problems asked in all sorts of cool ways. There are a ton of triangle problems using "angles sum to 180" facts and parallel lines and transversal problems.
Here's an example: picture triangle ABC. Then picture point D on segment BC. So you have your larger triangle separated into 2 smaller triangles. Put variables representing 5 of the 6 triangle angles (a,b,c,x,y). Let the 6th angle be 50 degrees. The question asks find a+b+c+x+y.