It's easy to forget on Wall Street. Stuff gets popular. Stocks jump. The money moves on, and things simmer.

But I've got a longer memory, especially when it comes to keeping track of some of the spicier meatballs out there, and it was with that in mind that I recently checked in with HokuScientific (NASDAQ:HOKU).

Some Fool readers may remember this as one of the rockets of last fall, when a pump by Jim Cramer and some rather convenient analyst comments shot the stock from $6 to $12 in short order. When I urged caution, I not only got the usual load of email about "bashing" the Next Big Thing, I got some feedback straight from one of those Wall Street firms that had taken Hoku public, then pronounced the stock a great deal.

How do things look now? Well, from an operational standpoint, they're a bit of a yawn. Hoku's revenue picture is working out more or less as last fall's filings predicted. There's slow progress, but nothing more than the meager revenues usually afforded to a company that is, despite its public nature, still a research outfit.

The stock, on the other hand, hasn't been as kind. Unfortunately for those who believed the yahoos yelling "Hoku to the moon!" at $12, the firm's shares have dropped a long way.

It's a story we've seen plenty of times before, even in the same industry. The fuel cell game has lost investors countless millions by promising an oil-free future. (Where ya gonna get the fuel for these cells, again?) Just take a look at the long-term performance of this crew: Ballard Power (NASDAQ:BLDP), Plug Power (NASDAQ:PLUG), Millennium Cell (NASDAQ:MCEL), and FuelCell (NASDAQ:FCEL).

Of course, none of this means that Hoku won't be a long-term success. But it does point out the folly of investing in gee-whiz energy technology in the midst of an oil-price scare. If Hoku really is going to change the world, I guarantee you there will be plenty of time to get major profits when Hoku's got proof of a product that will actually sell. Until then, watch your wallet, and keep your eye on that February lockup expiration. What's going to happen when 12.6 million (of 16.3 million) shares get out of the lockup, allowing insiders to sell their IPO shares? Who knows? But here's one thought. If the holders decide they need to start "diversifying" out of their fledgling company, it's not a good sign.

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Seth Jayson is always very wary of the Next Big Thing, especially when Cramer's touting it. At the time of publication, he had no positions in any firm mentioned here. View his stock holdings and Fool profile here. Fool rules are here.