I see that you asked about specialty rulers. My favorites are the CG ones for ruler cutting. The 6.5 x 24.5 is most used including ruler folding fabrics. The smaller ones 3.5 and 4.5 x 12.5 are all on the table too. The round ones are great for cutting corners on bags or pillows.
I couldn’t do without the large square rulers for squaring up quilts.
Love the flying geese rulers from Eleanor Burns. There is also a set to use for scallops, ribbons, and curves. They are seldom used but still a favorite. Guess, you could say ruler junkie here.