Mix Master All the way! I love it i make heaps of cookies and cakes with it. Its the most legendary cooking appliance around. The way you can just save time with it really tops it off.
Well, I love my Food Saver vacuum sealer, my 1980s Black and Decker food processor, my Wolfgang Puck mandolin, and my Taylor probe meat thermometer. I buy in bulk and save big bucks with the vac sealer, make mountains of cookie dough each holiday with the food processor, turn out perfect medium-rare roast beef with the thermometer, and cut exquisite cole slaw and cucumber/onion salad with the mandolin. Cooking life wouldn't be complete without my meat grinder, pasta roller/cutter, juicers and blenders. Really, it's hard to prioritize - like where do you rank the crock pot and the rice cooker. Don't forget the bread machine and the deep fryer.
I think it all depends on which cuisine(s) you prefer. I also have a pannini press and a gas grill.
I admit to being a gadget freak, but I passed up the spiral potato cutter. I get points for that, right?