I did Jerusalem in Fall, but I wish I had done London, too, and even somewhere else - the only time in your life when you can live abroad for a longer period with only yourself to worry about.
3. Other's have said it, but Personal Finance should be mandatory - Mortgages, Credit, Investing, etc...
4. Wish I had been more plugged into the entrepreneurial set at BYU...came from a house with a father that was a corporate guy - same company for 30 years...now that I own my own business, I wish I had explored that a little more at BYU...