You probably have it already lying around the house.
In my culinary school kit, we had two whisks. The first was a large balloon whisk, and the second was a slightly smaller whisk in the same shape for sauces. We used those whisks in almost every class—French cuisine involves a lot of whisking—but it wasn't until the last day that I thought to ask about a weird metal appendage on both of them. The whisks look just like the ones you could buy at your local big box stores, except for one thing—both have what looked like a plain key ring attached to the tips.
I assumed that it was for hanging the whisk up, maybe, or it was something the whisk was packaged with that and you were supposed to remove it. In fact, on one of my whisks I took it off and threw it away—the other I kept forgetting to address. It wasn't until the last week of class that I thought to ask our chef-instructor what that doohickey actually was. Turns out it's not for hanging the whisk up or for throwing away (oops). It's meant to help you whip things along a little faster—give it a little extra oomph. But not to worry about the one I mistakenly tossed, he advised. I can just go to the hardware store, or dig through a drawer, and find a plan keyring with no attachments on it. wash it, and add to the tip of the whisk. Voila!
The extra ring at the tip of the whisk really does make whipping go faster, but of course, if you're hand-whipping something, it's still not going to be as fast as by machine. That said, if you're too lazy to dig your blender out of the back of the cupboard, but not too lazy to find a key ring in your drawer, this will help you get through whipping cream or emulsifying a sauce that much faster.