The sign I use inside the O in Peko, and as a stand-alone on buttons, records, the web-site and so forth, is a lower case 'f' from the font Bullets 4 Japanese (bullets4.ttf)
I first started using it sometime after 1996, when flamencopeko.net (became peko.net) was launched, and the band had changed name from Stanley The Parrot to Flamenco Peko. F is the first letter in Flamenco. The name of the font includes the word bullets because all the signs have circles around them. The font is true type format. It is unknown who made it, and exactly how to categorize it. It is fixed-width. Could possibly be seen as a kind of dingbat. The term sans-serif might be applicable, although that is more of a western thing. An easy way to remember which rotation is correct goes: The loose parts are the top. The sign can display directly in utf-8 with for instance Arial. A hand-drawn, by me, version is in the footer of this site. I usually use the sign with the circle, sometimes without.
Despite my trying for years I was not able to find the meaning of the symbol. Even worse it turned out that this is number 61 of 2500 most used kanji in newspapers. It is amongst the first letters you're taught in school. Richard Andersen pointed out Friday 15-11-2013, via Thomas A. Thorvaldsen, that the Flamenco Peko sign, 米, (ç±³), (mÇ), (close to mi), is the Chinese character for uncooked rice
, husked seed and other grain-like things. It is also used for meter. I made this page and a 12 x 12 pixels version (actually 9x9) for my icons project
the same day. I've been using it on everything since like forever, so great to finally know what it means. Big up thanks to Mr. Andersen. It's being used in China, Japan and Korea. Fits quite nicely with my new-found appreciation of C-pop, J-pop and K-pop. Also I drink rice-milk instead of cow-milk. And if I smoked I would probably prefer rice-paper to wood-paper. Incredibly stupid of me to use a sign I didn't know the meaning of, but worked out quite all right. Even tattooing Asian signs we do not know the meaning of is in fact very common in the western world. We usually do this because someone told us it means something that it doesn't. We are now the famous rice band!