Seagate's magniloquently monikered Momentous XT has finally arrived in the TechRadar lab, sporting both traditional spinning platters and a chunk of flash memory, resurrecting a concept we'd long dismissed as vapourware.

It's the first hybrid drive we've seen for years: a statement which will make younger readers ask, what's a hybrid drive?

Back before solid state drives became the preferred option for every laptop from the ASUS EeePC to the Alienware M11x, hybrid storage was the Next Big Thing that everyone was excited about.

Drives made entirely of flash memory, like the Kingston V+ series, had been conceived and generally approved of, but everyone assumed they'd be too expensive to be of any practical use for quite some time to come.

While we waited for NAND flash prices to come down, so the theory went, hybrid drives like the Seagate Momentous XT would help sate demand for more performance. Hybrids have both spinning platters for large amounts of cheap storage, and a chunk of solid state memory for speedy access and a performance boost.

Theoretically, they are the best of both worlds, with all the advatanges of both SSDs and traditional disks.

But their time never came.

Before a decent hybrid ever went on sale, solid state prices crashed and the public decided that they didn't really care about the performance difference between traditional and SSD storage anyway.

Or did they?