I work on Wall st. As many others have already pointed out, excel is the bread and butter of many in investment banking and finance. The power and flexibility of excel cannot be underestimated. At the same time, with all the new regulations/Dodd Frank blah blah, there is a lot of discussions about adding "control points" around these mega spreadsheets/macros/VBAs that are used by Traders. I personally work with traders who use an Excel based addin to push trades into downstream systems.

Few days ago, I built a very simple VBA utility that queries an oracle database to give me relevant transaction information. They love it and I am the superstar already. Reason: this requirement was discussed with IT teams, sent to priority queue for months. After building this macro which took me 2 hours, traders got what they wanted without going through an IT budget.