I have a few...
My Cutterpillar Glow light box/cutting mat - this thing is amazing! I had suggested to my Mom that she should get an LED light box for tracing embroidery patterns. Instead, she got it for me for Christmas. Someone at my quilt group said it would be good for paper piecing, so I gave it a try. I will never paper piece without it again! Being able to see through to check fabric coverage, and cut right on the lighted surface is amazing. It also has a built-in battery, so I don't need an extra outlet to use it at quilt group.
I also love my Martelli products (cutter, mat, fmq hoops) and the Quilter's Slidelock - all worth every penny!