I like the Fons and Porter one Indycat talked about and really like it.

I like the Wonder Cut ruler, You cut two strips and sew together and cut them apart but placing the ruler and cutting.
very quick and simple. Plus it does other squares. Here is the web site for demos wondercutruler.com

Block loc rulers are the best I've found for squaring up half square triangles.

The only way I've been consistently successful is Brenda Henning's Triangulations! I own the 3.0 version, it's a CD-Rom half-square and quarter-square triangles construction 1/2" to 7.5" in 1/6" increments. She also includes tamed flying geese 1/2 X 1" to 3.75 X 7.5"

www.youtube.com/watch?v=0z6o7Bh7MYg

For some reason it won't link but if you copy and paste the above addy... will take you to an overview from Connecting Threads. She is showing the 2.0 but they are now selling the 3.0 that includes the Flying Geese.

Thanks for the reminder. I have the triangulations cd but never used it. totally forgot I had it. lol. I can use it with the loc block ruler.

June taylor perfect half square triangle ruler it squares them up as well as has a line so you can draw the lines in the middle of fabric to sew you have to see it, its like a shape cut ruler its nice I am getting one

I think the idea was to use a jelly roll and make both squares and half-square triangles from the same strip size that would fit together. Yes, you can use the Easy Angle ruler and use a 2 1/2 inch strip to make 2 in finished half square triangles. YOu can also use the omnigrid 98L to make right triangles from strips also.

Gale, I love my Loc-Bloc ruler. My HSTs were never nice until I invested in this great tool. You won't be disappointed.
peace