I first came across this very handy little sewing room extra on Ami Simms 'Through The Eyes Of A Quilter' blog at http://amisimms.wordpress.com/ and being a bit of an Ami Fan I just had to try one of these little handy dandy's out.
Of course, here in Aus. it wasn't the bargain buy that Ami Simms was recommending, but I managed to track one down that wasn't an arm - leg - mortgage the house option and I have to say its a little ripper........er pardon the pun.
The stitching threads get cut by the little teeth, much as pet fur does, which is what the Whal Pocket Pro Pet Trimmer is designed for. As with all things magical, it has its little personality traits, the fabric has to be kept flat and the stitches at a firm tension to allow the little teeth to slide in.
And these are the little extras you get in the pack. Guide combs, cleaning brush, oil and even a battery, oh and that black square at the top........not a clue, just came with the piccie. You can get them from Amazon or any Vet.
One of those 'how did I live without this gadget' type of things, just make sure you research the price.