When the Fleischmann/Pons experiments did not pan out in the late 1980s, the subject of cold fusion more or less disappeared from respectable scientific discourse. Nevertheless, research has continued in a kind of underground fashion, and occasionally interesting if inconclusive results have been reported.
Now, Japanese researcher Yoshiaki Arata has apparently
...demonstrated a low-energy nuclear reaction at Osaka University on Thursday. In front of a live audience, including reporters from six major newspapers and two tv studios, Arata and a co-professor Yue-Chang Zhang, produced excess heat and helium atoms from deuterium gas.
So is an era of cheap, abundant, and clean energy just around the corner? Well, a few caveats have been expressed here:
Augustin McEvoy, a retired condensed-matter physicist...has studied Arata's previous cold-fusion experiments in detail. He said that he has found "no conclusive evidence of excess heat" before, though he would like to know how this demonstration turned out.
And here is a .pdf outlining the Arata's experimental setup. Looks pretty easy, in fact. I may crank up one of these on the weekend and stick in the Cavaliere.