I admit it, I've used a few words that have made people cock their heads like dogs hearing a whistle. I don't know what it is about slang and colloquialisms from the UK, but I must use them. I must insert them into emails and IM chats and every day conversation. I feel it's my duty to bridge the gap (one language separated by an ocean or whatever) and impart some notions of foreign communication on my fellow Americans.
I can't say what it is that appeals to me about it. I watched a lot of Doctor Who as a kid, listened to Hitchhiker's Guide radio shows and later became a fan of Whose Line Is It Anyway. Now that I've got comic/art acquaintances in the UK, I do my best to use it. I guess as a way of showing that I'm not a Bush-loving cowboy or whatever stereotype they may have of us.
So if you hear me use words like "sussed" "dodgy" or "nackered", please realize I'm not trying to be fancy or purposefully odd. I just like their words better. I mean really, which would you rather say: "I've got it sussed" or "I've got it figured out." I'd rather say "cheers" than almost anything else to end correspondence. Nothing I say, however, makes it sound as good as when it is said by native purveyors of the language. In speech it sounds like I'm trying to hard. I'm sure in writing it makes me look like a nutjob.
But even if it wasn't UK slang, it'd be something else. I'm the only one I know in my circle to say "groovy" or "ciao" or "dag nabit." I've substituted sci-fi swears where possible, but I'm not John Creighton or Lee Adama so it still sounds wrong. Doesn't mean I won't try. As a plus, it's better for my kids to hear "that's frelling ridiculous" instead of any alternative. LMA has some imprint that doesn't allow her to say "shut up" or "stupid" without asking for a bad-word-pass, so while I slip up more than most, I'd still like them to understand that slang and curses are more about emphasis and how you feel saying them then the actual word. Odd that it's the actual word that gets you in trouble. I can promise you that a first grader saying "frak me" will still draw attention, but guess what, it's not against the rules.
On the other side of the coin, none of the guys I know across the pond use that much slang in forums or on chats. Frankly I try to use their words because I feel bad that their using mine so often. I can't hear a Brit actually saying "awesome" but I know they type it. I have a friend in Finland who I'm sure has fantastic words for "cool" and "that sucks" but he seems to have a better command of English than I do and doesn't seem to want to change that.
I need a bumper sticker that says "I Heart Polyglots."