What started out as a moderately useful gimmick to view the entire width of a Web page or a photo in its proper landscape ratio has turned into one of the iPhone’s greatest assets. With the overwhelming success of the App Store, iPhone’s accelerometer suddenly has a million and one uses, turning the handset into everything from a fishing pole to a plumb bob--even a tectonic plate.

Here’re 12 of our favs:

iBeer/iMilk/iSoda

A simple sight gag, sure, but we can’t salute the accelerometer without paying a little homage to one of the original novelty acts. While not the cheapest of thrills at $2.99, these three apps are the best possible advertisement for the brilliance of iPhone and the technologies therein. Tilt the phone to “drink” the beverage; shake it to create more suds--or heavy cream, in the case of iMilk. Turn on “dirty mode,” and your beverage will even leave behind residue as you pour it. How cool is that?

Instapaper

Even if we overlook how our new favorite app has made our iPhone that much more indispensable, we have to take a moment to praise one of the most ingenious implementations of the accelerometer we've ever seen: tilt scrolling. After collecting a handful of Mac|Life articles you couldn't get to during the day, Instapaper presents each one in a neat, easy-to view format that can be read from beginning to end without ever touching the screen; turn on tilt scrolling, and you can pan through the story simply by tipping your iPhone ever so slightly--or farther back for you fast readers. It's so brilliant, you'll fret ever having to turn a page again.

Snail Mail

Winner of IGN’s Best Use of Accelerometer award last year, Snail Mail is the quintessential iPhone game, leveraging iPhone’s tilt controls to put you right in the center of all the slithering action. Like Need for Speed, your snail mailman is controlled directly by accelerometer movements, but there’s more to this game than simply staying on the track--any number of obstacles, enemies, weapon rings and power-ups await you around each twist and turn, and the game’s precision tilt controls make it a gooey guilty pleasure.

Labyrinth

Like a classic that never goes out of style, the ol’ guide-the-ball-to-the-hole-at-the-end-of-the-maze puzzle game never gets tired. It was fun when it was carved out of a wooden box, and it’s nearly perfect as an iPhone app. With precision accelerometer controls and realistic gameplay, you just might forget there isn’t actually a tiny silver ball clinking around inside your iPhone.

iFishing

While most captains are lured to Flick for their off-the-water flounder fix, it doesn’t win our award for Best Use of iPhone as a Fishing Pole. That distinction goes to iFishing, which recreates the experience with a bit more realism, casting your line based on the actual direction of your flick, rather than assuming a straight toss. And once your hook is in the water, iFishing handles the natural movement of the rod better, too, mimicking the subtle jerks and tugs of the open water, while also responding to the fisher’s own movements. Just like a fishing boat, without the nausea.

ShakeItPhoto

Digital photos may be superior to film in most every technical way, but there’s a certain nostalgia that today’s cameras can’t recreate. But thanks to iPhone’s accelerometer and a little out-of-the-box thinking from Nicholas Campbell, the tedious, yet-oh-so-satisfying completion of a cropped, dated Polaroid snapshot can now be enjoyed without carrying around a clunky instamatic camera. And you can even listen to “Hey Ya” while you shake it... shake it... shake it like... well, you get the picture.

iHandy Carpenter

Of course, we wouldn’t recommend using iHandy Carpenter for any major construction projects--and we’d toss out any contractor who tried to convince us of its benefits over an actual set of tools--but that doesn’t mean it won’t come through in a pinch. Accurate to one-tenth of a percent, iHandy utilizes the precision of the accelerometer to transform your handset into a makeshift level, plumb bob, protractor and steel ruler. iPhone’s curved edges and aerodynamics make for a tricky implementation of said tools, but it’ll do a bang-up job if you need something on your wall straightened.

Pocket God

As ruler of a small island nation of a seemingly unlimited amount of resilient, relentlessly good-natured pygmies, Pocket God takes advantage of every iPhone technology to put an arsenal of horrific situations at your fingertips. But it's the simplest ideas that work best, like tilting your phone to send your pygmy sliding into the water or shaking it to create an earthquake. And after your done torturing him, turn your iPhone upside down to put him out of his misery. Now if only there was a beehive in the coconut tree...

Dr. Awesome

It takes a steady hand and a keen eye to become the world’s most popular microsurgeon, and Dr. Awesome puts all of your skills to the test. A nice departure from the accelerator-based maze, puzzle and racing games that populate the App Store, your task as Dr. Awesome is to cut viruses and bacteria out of infected body tissue using iPhone’s accelerometer to deftly guide your scalpel. Who knew your iPhone could save lives, too?

Need for Speed Undercover

The absolute cream of the racing game crop, Need for Speed puts you in the driver’s seat of some of the world’s fastest cars, replete with all the drifting, nitrous boosts, speed breakers and customization from the best-selling console version. Immersive graphics, realistic rack-and-pinion steering and precise, high-performance handling make for a smooth ride in your whip--at least until the phone rings, anyway.

Dynolicious

We don’t exactly have access to a quarter-mile stretch of track to play with, but judging by our pitiful test results, we’re pretty sure our 175hp Nissan Altima isn’t the type of whip Dynolicious was designed for--but that doesn’t make us feel any less fast or furious while using it. By using iPhone’s accelerometer, Dynolicious is somehow able to measure your car’s G-forces to determine acceleration and vehicle performance. It might not stand up to the Racelogic’s Velocity Box, but at a $487 discount, we’re not complaining.

Rollercoaster Rush

The iPhone version of one of Digital Chocolate’s most famous games is pretty much what you’d expect: fun, challenging and addictive, but with one notable improvement: Instead of wildly tapping the screen to speed up or slow down your cart, DC has tapped into the power of the accelerometer to reduce the strain on your index finger and increase the control over each track. Simply tilt the phone forward to dart ahead and tilt back to hit the brakes. Believe us, it’s way more fun than it looks--and not nearly as easy as it sounds.