" I'm an exceptional programmer in the language I know best, but it is not Ruby." "Your friend would not consider hiring me because of this "
I don't know how exactly you define exceptional, but if you are indeed exceptional in the sense of being in the top 5% (say) of developers in your chosen language, and assuming your language is not some forgotten relic from the 60's, then you should be beating off employers every day.
If I wanted a game written in Java (for whatever reason) and John Carmack wanted to take the job but he knew only C/C++ (but was ok with learning java) I couldn't imagine turning him down because I have Joe Blow's cv showing 10 years experience in java. If you are really exceptional in your language, I doubt someone would turn you down just because you'll take a couple of weeks to pick up ruby.
Moving on, I wonder how came to the conclusion you are "exceptional"? This isn't a mocking question. I am just curious because even though I am a good programmer (if I do say so myself), and I have improved a few quanta of magnitude in the last few years, I always find that there are many people much better than me,no matter what level of proficiency I attain.
Maybe I just don't work hard enough but I am very interested in knowing at what point one would classify oneself as exceptional (vs other people making that judgment).
What have you achieved in your language of choice that made you conclude this? Maybe you have some code out there we can look at?
"Your friend would not consider hiring me because of this too I'll bet -- yet I could probably build his site twice as fast as the best Ruby programmer."
This doesn't compute. The best ruby programmer in the world (whoever he/she is) should be massively productive. What enables you to get a 100% boost as compared to him?
EDIT: On judging oneself exceptional. There is a local legend that goes like this.
Once upon a time, long ago, a prince told his father(the king) that he wanted to become a martial arts expert and an exceptional warrior. So the king apprenticed the prince to the best martial artist in the kingdom. The master was a greet teacher and the prince was very talented and diligent, and he threw himself into the training. The king got regular reports from the teacher that the prince was steadily advancing in his proficiency.
A year later, the prince came home for a holiday and the king asked him how his training was going. he replied " I've learned a lot. I could take on a 100 opponents at a time and win, easy". The king said " That isn't good enough. You need more training"
The next year the king asked the same question and the prince replied " well I've learned a lot more and I've changed my estimate. 100 people may be a little tough but I can take on 50 and win" and the king just shook his head sadly and asked him to train more.
Every year after that the king would ask the same question and the number of people the prince thought he could fight simultaneously kept coming down till after many years he replied "I think I could handle one opponent, maybe, but if possible I'd rather fight a duel only when absolutely necessary, because you never now what the result will be. There is always the possibility that your opponent totally outmatches you."
And the king replied " Now your training is complete". (And by then the prince was indeed a deadly fighter, the best in the kingdom).