I guess mine would be our Cuisinart stick blender. Both DH and I use it for creaming soups, smoothies, cake batter, salsa, gazpacho- so much easier than dragging out the Kitchenaid or large blender. We packed it away accidentally and have missed it [although it is too hot here in our rental for soups or baking.] Also, I have had a Dualit toaster for three years and now realize how much I miss having a toaster oven. So I plan to ditch the Dualit and buy the Krups digital toaster oven, once we move back into the house.

Good kitchen scissors and shears. Heavy duty, they must come apart so they are washable (dishwasher).

Santoku knives, microplane, KitchenAid stand mixer and food processor.......oh and a 3 1/2 qt. saute pan.

I would also say my cuisinart stick blender is one of my favorites. I don't think it necc has to be a cuisinart, but one with a metal shaft, so you can use it in hot soups, etc. is important to me. I always had the plastic ones before and I had to wait until the soup cooled enough and puree it in the blender, then heat it back up again. This is so much easier.

I also like having the dishwashable plastic cutting boards from Ikea. I have had other ones, but my knives cut through them. The Ikea ones are thicker than most. I only use my wooden cutting board for non-meat items, and the plastic ones I use for meat, and for fruits so they don't pick up the onion/garlic odors from the wood one. They are also handy because you can use them to funnel the cut foods into a container easily.

I like my rice cooker (a little cheapo one) too, but I wish it were bigger. I always had trouble consistenlty getting rice right, in spite of trying the dozen ways that people told me to do it.

I have a collection of gadgets, but the one that has changed cooking the most is probably the fuzzy logic rice cooker that I got in Jan.
Rice is so simple that it becomes a part of more meals. Plain white and sticky rices are great. I had guests rave about white rice last week that I put in just in case we needed more food.
My current infatuation is pilaf experimentation as follows:
With this type of cooker (not the steamer style) you can just toss in some nuts and butter or oil to brown, add some veggies (onion, pepper, shallots, carrots, etc) to sweat, then add the rice (use a stock instead of water if you wish). Add seasonig and herds to taste. Out comes a delicious pilaf. Add some raisins if you want it sweeter.
No mess, no fuss, all in the cooker.

Food Processor
Flexible cutting sheet
Toaster Oven
Stick Blender
Microplane

My ancient, original food mill. Amidst the array of new-fangled kitchen appliances I have amassed, it's still my favorite.

Kitchenaid mixer, hands down.

I have a favorite knife....looks like a chef's knife but is ~5" long...it's a Martha Stewart basic and I got it at Kmart years ago. I love it more than the more expensive knives I own.

BUT, the one thing I'd take if I had to leave everything else in the kitchen behind would be my Tassimo coffeemaker. I like it because it makes a great cup of coffee, of course, but you can make tea & hot chocolate too. I make mocha with it that's a wonderful treat.

I use my mixer and food processor a lot. The microplane is useful for several things and I use my garlic press often.

However, the "gadget" I probably use everyday is the Mario Batali prep/measuring bowls. I have 2 sets now since I find them so useful. I was looking for some new prep bowls and found these at a Sur La Table in my area. The fact I can use them to measure things as well as prep bowls is great.

In order of most use:

Krups programmable coffeemaker w/thermal carafe
All-Clad stainless 3 qt. saute pan w/lid
Forschner-Victorinox chef's knife (so cheap and fabulous!)
Plastic cutting mats w/silicone grippy back
Williams-Sonoma nesting glass bowl set w/extra prep bowls
Wusthof kitchen shears (the basic ones)
Silicone spatulas/spoonulas
Oxo measuring cups you can read from above
Mini food processor (used mostly to make vinaigrettes)
Microplane grater/zester
Old-fashioned glass citrus juicer
Set of footed mesh strainers in graduated sizes
Small marble mortar and pestle
Electronic kitchen scale
Le Creuset baking set (assorted casserole sizes)

I have other appliances/tools I love, but these are the ones I reach for most often.

On the other hand, here's what I rarely use:

Ice cream maker
Toaster oven
Salad spinner
Pasta pot
Blender (this is my husband's favorite, though, for smoothies)
Full-size food processor (though it's great when it's needed)
Standard metal cheese grater

This will sound silly, but I have found the Swing-A-Way jar opener to be really handy to have around. Nothing will open a stuck jar as easily as this gadget--you won't have to bang the edge of the jar, or run hot water over it or anything. And for $3.99, it's a deal.

Here is a link that might be useful: Swing-A-Way Jar Opener (Click on Photo to Enlarge)

Kitchen shears (A MUST - use my two pair daily and dishwasher safe)
A Pastry cutter (great for egg salad in addition to pastry)
and
Several Cutting boards (I use the white non porus? type)

Hot Shot hot water heater. It's ugly, but far quicker and easier to use than a kettle, and much cheaper than a built-in hot water tap.

My husband uses our 18-year-old toaster almost every day.

These are a few of my favorite things...in no particular order:

A good set of knives
Oxo peeler
A bamboo spatula for sauteing and wok-cooking
A Cast-iron skillet
Having several sets of measuring spoons (not just one)
Electric kettle (Braun)
My new! le creuset french oven
A few plastic (rather than wood) cutting boards i can throw in the d/w
All-clad 2-burner griddle--love it!
Various sizes of whisks
Baking stone (for bread)
The huge cookie sheets that came w/my wall oven
Miracle cloths--great for cleaning granite counters and ss appliances and sink

Good luck!

When we bought a second (lake) home with a small kitchen, we looked around and said "what can't we live without in the kitchen?" and then stocked the smaller house with the most important items:

Digital scale - we use it for measuring flour and other dry ingredients for baking. Also, you can slip a rubber band over fettucine or spaghetti and weigh exactly how many ounces you need, and the list goes on and on.

Good knives
Lots of measuring cups, individual prep bowls (small to large)
Wooden spoons
Le Creuset Spatulas
Cast Iron skillet - mine is Le Creuset
Cast Iron Dutch Oven - ditto
Caphalon nonstick saute pan
Caphalon sauce pans - 1.5, 2, 3 quart