Each Spring, the Nürburgring opens its gates to car manufacturers eager to flog their winter projects on track for the first time. Needless to say, this time of year draws throngs of photographers to the circuit, who sell snaps of car companies' camouflaged prototypes to motoring journalists hot for a scoop.

This was the scene, back in March, 2011, when BMW showed up at the famed German racetrack with an E92 M3 pickup truck.

The timing couldn’t have been better. Knowing the spy photographers would be out in full force on the first industry days of the year, BMW engineers wrapped the pickup in standard, spy-thwarting camouflage and did some hot laps; all while laughing inside their helmets. After all, it was less than a month before April Fools Day.

Naturally, spy photographers did what spy photographers do: they sold their shots of "the first ever BMW M3 pickup" to car magazines and blogs around the world. Us goofy car journalists took the bait, and we were dumbfounded. Was BMW insane? Had they built an M3 ute for Australia? Was the nascent El Camino market in the US secretly heating up?

Negative. The car was never meant for production, but it was a standard E92 M3 Convertible. The hard-top roof and trunk were replaced with a truck bed. It was an after-hours project for those at BMW M. And while the odd M3 became an April Fools joke of epic proportion, it also had a purpose: With its bed of gleaming diamond plate, engineers and techs at the BMW M campus outside of Munich used it as a shop truck.

These days, the M3 pickup resides at BMW M’s headquarters, along with a panoply of strange prototype vehicles you’ll never see at a dealership or museum. There are cars and SUVs made by BMW engineers for various reasons—development exercises, product studies, and the like—but are rarely seen.

I got to drive the M3 pickup for an upcoming /DRIVE on NBC Sports episode, and it was as bizarre as it looks. With more than 12,000 kilometers on the clock, it's obviously been well used. And we've all learned a valuable lesson. Maybe.

Check out the /DRIVE on NBC Sports BMW M special episode this Friday, October 21 at 6:30pm ET on NBCSN.