The original idea came from this video
http://youtu.be/KZn4MuXwNhA
But instead of using glass, I decided to use acrylic. This is a fail because I used acrylic meant for picture frames and it had an anti glare coating that made the acrylic look frosted.

Step 1: Gather Supplies

Acrylic -$6 do not use the Anti glare picture frame stuff
Black silicone/vinyl -$5
Acrylic cutting tool -$5
Copy paper
Straight edge
Marker
Hot glue gun -optional
Clear tape
Caulk gun

Step 2: Make a Template for Your Triangles

The bottom of my triangles were 7 inches and they were 9 1/2 inches tall. My acrylic sheets were 14x11 so I cut them in half to 7x11 sheets. I marked the middle line then drew a line across 9 1/2 inches from the bottom. I drew a line from the corner to the intersection of the lines. For the bottom piece, I measured the center line then measure 7inches from the bottom corner to the center line. There should be 3 side triangles and 1 shorter, bottom triangle.

Step 3: Cut the Plastic

Line up a straight edge with a line. Clamp the straight edge to the table. Tip- have the straight edge covering the part that you want to keep. The tool curved away from the straight edge a couple times. It took around 10 swipes to cut through the 0.05 inch thick plastic. If the plastic isn't cut all the way through, bend it over a sharp corner for a clean break. Cut on a surface that can get marks in it, the tool may leave marks.

Step 4: Assemble

At this point, I peeled the protective plastic off the acrylic and it was revealed that the surface was frosted. I kept going with the project to see how it would turn out.
Lay the base triangle down and align the sides down flat. Tape the sides to the base then fold them up. I used hot glue to tack the corners then I ran a line of the silicone down the side using a caulk gun.