Welcome to Underappreciated, a showcase for outlier vehicles from the late 20th and early 21st centuries, cars that presented fresh ideas or innovative technologies but failed to connect with consumers then and remain undervalued (read: bargains) today.

Infiniti was a bit troubled at the end of the 1990s. Unlike its competitors from Toyota (Lexus) and Honda (Acura), after its first decade in the U.S. market Nissan's upscale brand had failed to crack the magic 100,000 annual sales mark. In an effort to boost its fortunes and image, the brand added the midsize M45 (internal code Y34) sedan in 2003.

"The M45 was available for only the 2003 and 2004 model years, in which a total of 8,067 were sold. "

The M was intended to patch a medium-size hole in the Infiniti sedan lineup, slotting between the smaller G and the larger Q. Like similar vehicles from its German and Japanese brethren—E-Class, 5 Series, GS—it was a step up from entry level and a step down from top tier. But its core play was its performance-to-price ratio. With a base price of just $42,300 and a naturally aspirated 4.5-liter V-8 from the Q-ship providing 340 horsepower and 333 lb-ft of torque, it was close in output to high-test executive sedans from the likes of Mercedes-Benz's AMG or Jaguar's R subbrands but at a cost closer to their basic six-cylinder models.

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"The M45 had the power and performance of the Q45 flagship, as well as many of its luxury appointments, in a lighter, less expensive package," says Kyle Bazemore, director of communications for Infiniti North America. "And the output of the M45's V-8 was quite impressive—in fact, one of the highest power ratings of any standard, non-specialty engine on the market at the time."

Featuring a bit less mass than its big brother, the M45 was able to hustle to 60 mph in about 5.7 seconds, which was quite an achievement for the time. Perhaps more important than this was the way the M45 looked. The sedan had a beveled front and rear, muscularly rounded flanks, and a pert if lengthily overhanging tail that conspired to give it a kind of sneering American menace. It looked like a modern interpretation of something Elwood Engel (Chrysler's design chief during the mid-'60s) might have penned, along the lines of a scaled down Imperial Crown sedan: angular, squatting, wide-eyed, and ready to roar.

"It doesn't look like anything else, I knew it was rare. But nobody knows what it is. "

"It doesn't look like anything else," says Joe Wu, a 19-year-old college student at University of California, Riverside, who stumbled into buying the 2004 M45 you see here for $3,000 when he was looking for a Lexus LS 400 to act as his daily driver, a way to keep miles off his 1986 Toyota MR2. (The M45 has roughly 131,000 on the odo). "I knew it was rare. But nobody knows what it is, so I thought it was interesting."

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Alas, this contentious design was in many ways the car's Achilles' heel, as it didn't resemble anything else in the Infiniti lineup. This wasn't exactly out of the ordinary. For much of the brand's first decade, its styling was somewhat grab-baggy in its diffusion—a blocky convertible next to a sleek executive sedan next to an inflated truck-based SUV next to a spruced-up front-drive commuter. This was the result of Nissan's proclivity for poaching an existing if sometimes outmoded Japanese Domestic Market (JDM) vehicle, stuffing in a bigger engine, and slapping on a gaudy Infiniti badge. This was certainly the origin story for the M, which began its life as a V-6-powered Nissan Gloria. Sadly, the M's retro-inspired styling, while au courant in the industry at the time, with VW's New Beetle and Ford's Thunderbird redux, didn't sit well with customers who were in the market for a contemporary Japanese near-luxury offering.

What those customers apparently wanted was a high-riding, cramped, all-wheel-drive hatchback shaped like a creasy high-top sneaker. Something like the trendsetting Infiniti FX sporty crossover, introduced about the same time. Although annual sales of the Y34 generation of M45 peaked at just more than 4,500 units in 2003, the FX immediately sold at an annual rate of around 30,000.

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"The M45 was available for only the 2003 and 2004 model years, in which a total of 8,067 were sold," Bazemore says. "Each of these represented incremental sales to Infiniti, which would undoubtedly be lost to other luxury brands. But for 2005, the Infiniti M line was completely redesigned to have more of a familial look with the [then-recently] introduced G sport sedan and FX performance crossover."

This new sedan (internal code Y50) featured smaller exterior dimensions, more interior space, and a more conventional and amorphous design. Consumers responded by buying 24,000 of them in the first year. All of this conspires to make the Y34 not only relatively uncommon but also a car that many people are entirely unaware of. This will work in your favor if you want to buy one.

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These cars were pretty loaded when new, featuring lots of leather and wood, sophisticated tech such as xenon headlamps, speed-sensitive steering, laser-distance cruise control, heated and cooled front seats, and a signature garish Infiniti analog clock. Still, searching online automotive listings revealed a number of well-cared-for cars with less than 100,000 miles trading in the mid-four-figure range. This low price will net you a thrilling and exclusive competitor to Aughties Germans. Plus, it will provide a point of access to those cool vintage Japanese car shows.

"It has a definitive 'JDM' look that captures the eyes of tuners that grew up with Japanese hot hatches and who chose domestic-market-only cars to 'drive' in 'Gran Turismo,'" Bazemore says.