One of my favorite things about a quilt retreat is that everyone is so relaxed and generous. Not only is the advice and inspiration plentiful, but everyone has different tools and notions they're more than willing to allow you to experiment with.
I purchased a Martelli Rotary cutter after my retreat buddy Kathleen showed me hers. Now Kathleen is left handed and found this to be most comfortable for her. I on the other hand have tried lots of different cutters. I like a blade that stays out not the pressure sensitive ones. My major problem has been that I have large hands and no matter which I tried, my hand or finger would inevitably hit the safety button as I was cutting and I would bash my knuckles against the cutting mat and if I was extremely unlucky that day, the ruler would slip and I'd ruin a piece of fabric. Now I find that I have more control, my hand doesn't get as tired as quickly and I can cut through lots of layers of fabric at once. It took some getting used to, but now I am a true fan of the Martelli cutter, next purchase will be a 60mm.
Along with the Martelli, I had the opportunity to use some rulers with Invisipgrip from Omnigrid. A thin clear non slip plastic that adheres to the back of your rulers to prevent slipping. Wow, that stuff was so great, i had to buy some. So it arrived today, the first ruler I applied it to was my 12½ x 12½" ruler. Awesome, couldn't wait to put it on my smaller rulers. I cut out one for my 6 x6 and another for my 6½ x 6½ and another for my 4x14 (this one would be a little small but I was confident that it would still work. Then I tried to get the darn invisible stuff unstuck from the backing paper...then my DH tried...then DS1 tried....then DS2 tried....then DSGF tried.....what was going on????? The first piece went on so easily! We all spent 30 minutes trying to un-stick this stuff from the backing, I was really POed, said screw it and went to make myself a cup of coffee. When the logical mathematical quilter in my brain could finally be heard....6x6, 6½ x6½ and 4 x 12 could all be cut from one 12½ x12½ piece!!!!!! I was trying to get double duty out of a single duty 12½ x 12½" piece! DS summed it all up when he said, "They don't call it INVISIgrip for nothing!" LOL