It's also the same character the forum is using a webfont to render in BTC.
Actually,
BTC is the characters "BTC" with the B made to look like
BTC and the "TC" invisible (using webfonts). So you can copy/paste it without losing meaning, even if Unicode isn't fully-supported.
This is a bad idea, because the browser isn't guaranteed to copy the invisible TC. Use ligatures instead to achieve the desired effect.