Hajikko
Hashi is a Japanese word meaning "edge" with two emphatic variations ("very edge"): hajikko and hashikko. Hajikko, the "voiced" version, seems to be more common in speech than hashikko, but why should this be the case when hashi's own voiced variant, haji, is so rare that I can't recall ever having encountered it in the wild?
I should probably admit up front that I didn't find a satisfactory explanation for this. The closest I came is a question at Yahoo! Chiebukuro hinting at an east/west divide: here on the eest side we say hajikko, out west they say hashikko, and there's one poster from Tottori representing hazukko. Well, hajikko does feel more Edo than hashikko...
While I was searching, I also found this great 2ch thread in which the participants snipe at the great unwashed (and, before long, each other) over usage -- "Osaka. Lots of people who say shuppai for shippai (mistake)" / "Nobody fecking says that, you tool" -- and talk about 『進ぬ!電波少年』 (Susunu! Denpa shōnen), a television program with a nonsensical name derived from its predecessor's『進め!電波少年』 (Susume! Denpa shōnen, "Onward, idiot boys!") by extending the loop on the め (/me/) to get ぬ (/nu/). Good times.
naoki:
Oh, really? I usually say like
Sokono haji ni aru yatsu totte.
I wont say hashi ni aru yatsu...
It feels like I bite my tongue saying so. For the record,
I'm from Tokyo.