Believe it or not, this is quite common in the industry. I developed some software for one of the Big 5 banks in Canada and I saw first hand traders learning to program using C++, Java, whatever they can get their hands on because they need to test out models, perform calculations that Excel can't do readily - although VBA is a trader's best friend.

Recently, they've been using R more and more. And as you'd imagine, their code is horrendous but hey, it works.

What I learned is that the entire financial industry relies on Excel and really bad programming. It's really scary to think that 37Signals has better software and software practices than a bank.