If you like to sew clothes or are wanting to start I would highly recommend this tool. It is wonderful.
The other tool I really like right now is my darning foot a.k.a. free motion quilting foot. I picked this up about a year ago and I have loved it. My machine is and older Bernina model so I was unable to get one with the stitch regulator on it.
I have discovered that I can do all kinds of quilting designs with it and with some practice I am doing much better at controlling my speed and stitch length. I can also do free motion applique with it. I am really enjoying it and experimenting with it.