My use all the time ruler is the June Tailor 6"x24".
My other frequently used one is the 16-1/2" Quilters Rule Square-Block Lap Board.
I occasionally use the 6-1/2"x24" Quilters Rule, but find it very hard to read.
I also like the Easy Hexagon by Sharon Hultgren.
Would like to have a 12-1/2" square one for convenience.
Would like to find a ruler longer than 24" and wider than 6-1/2" but haven't seen one yet.