Just been reminded of one of my current pet hates on R4 this morning. Scientists, mathematicians and IT people, often campus based, who start sentences, and often whole conversations, with the word "so".
It's as if they are picking up mid-conversation discussing proofs with a colleague, whilst also trying to convince you, in a patronising kind of way, that you have embarked on a level of dialogue of which they are master.
It's just plain irritating when such grammatical absurdities gain widespread use and are thought by the user to signify smartness. Quite the opposite IMO.