How about 'I could of' instead of 'I could have'? That always drives me wild, but I've found it in printed UK English back to the 1940s.

As to Raedwulf's comment about 'gay', I'm not sure from where he thinks the homosexual community hijacked it. Two hundred years ago 'gay' as an English adjective could mean 'randy or promiscupos or sexually available': as a verb it meant 'to copulate', and there were odd phrases like 'gaying pole' and 'gaying pintle' meaning the penis. The Victorian prostitute's come-on was 'Are you gay?', meaning 'Are you looking for sex?' and prostitutes were referred to as 'gay women'. I have a Home Office report of about 1910 which refers to prostitutes as 'gay women' and doesn't feel the need to explain or comment. I thought the modern usage by homosexuals arose because they were the last group to preserve the question 'Are you gay?' but gradually let it change its meaning, from 'Are you looking for sex?' to 'Are you homosexual?'