Sip, talk, sip, talk, wipe mouth with sleeve

I'm getting to enjoy my English lessons with M, a very talented Russian immigrant who has just got an amazing scholarship offer from a university in Holland, and therefore wants to improve her spoken English. She's painfully self-conscious when speaking English, but actually not bad once she starts sipping the ol' Tuborg. We just talk and talk and I throw in a few tips about letter writing, or new vocabulary etc. A nice way to spend an hour, and I get cash and free beer...hang on, there's a dream business opportunity in there somewhere...

Out of interest, in the good ol' US of A do they ever sign off formal letters with 'Yours sincerely' or 'Yours faithfully'? I'm presuming this is funky British English at its quirky best...