Did the Mac Pro case nesting trend go viral—has the old tower put the trash can back inside?

If hardware modding were treated as a sandbox experiment, this outrageous "Mac Pro" would probably win the day's award for Best Creativity. Reddit user u/blank_reg bought a 2010 Mac Pro on the second-hand market, and the seller only gave a brief warning in advance, saying there was something rolling around inside the case. But when the case was opened, it wasn't loose parts or a detached hard drive inside—it was an entire 2013 Mac Pro stuffed into it, the cylindrical desktop infamously nicknamed the "trash can" by users and the tech community alike because of its shape.

What makes this so interesting is not just the "Russian nesting doll" aspect itself, but how precisely it highlights the clash between Apple's design philosophies across these two generations. The 2010 Mac Pro was a classic tower design, with ample internal space and strong modularity. Its CPU, GPU, memory, and storage all offered a high degree of replaceability, and it could even be modified to support modern AMD graphics cards. By contrast, the 2013 Mac Pro took the route of extreme miniaturization: quiet, compact, and aggressively styled, but with an equally obvious tradeoff—its expandability was severely limited, making traditional desktop add-ons like hard drives and PCIe devices almost impossible to accommodate elegantly.

Judging from the available images, the 2010 chassis has actually been heavily gutted, with little left inside besides the power supply and front-panel I/O. The core structure that originally belonged to the tower workstation is basically gone. In other words, it looks more like someone built an oversized "external dock" for the 2013 Mac Pro, placing the originally closed-off cylindrical machine back into a physical space that can be tinkered with, wired up, and expanded further. The idea feels a lot like something players do in simulation or management games: if the system itself isn't open enough, you build another layer around it yourself and rearrange the rules.

That said, this "nested Mac Pro" is not a fully finished build at this stage. The original post notes that the inside of the 2010 chassis is currently almost empty, and the expansion devices that once surrounded the 2013 machine appear to have been removed. The buyer also did not disclose the sale price or say whether the two machines are still functioning properly. So right now, it reads more like a highly symbolic modding scene than a mature setup ready to be put to productive use immediately.

My own view is that what makes a case like this appealing goes beyond mere novelty. It reminds many longtime users and hardware enthusiasts that Apple once brought "modularity" to a very high level of refinement with the 2010 Mac Pro, while the 2013 model pushed industrial design to the opposite extreme. The result was a product line that went 6 full years without an update, only returning to the classic tower approach in 2019. For people who enjoy tinkering with old machines, this feels almost like a piece of design history made physical: one era gave up space for appearance, and another eventually had to reclaim that space.

If you're also looking at old Mac Pro models on the second-hand market, my advice is simple. First, don't judge only by the model year of the outer shell—make sure to confirm what's actually left inside. Second, old tower cases have high modding value, but that also means they may have undergone extensive disassembly and alteration. Third, extreme one-off cases like this are better suited for collecting and study than as a low-risk purchase. For ordinary users, it's a legendary story; for modding enthusiasts, it's more like a very blunt piece of community wisdom: when expandability is taken away, people will eventually put it back themselves.