When talking iPad with enterprise users, one of my favorite show-off apps for the iPad is MeLLmo's Roambi. It's a little hard to explain what it does, but once they see it in action, they know they want it. Roambi (free on the App Store, pro/enterprise plans available) gives you instant, easy dashboards for your data on your iPad, and it lets you share your numbers in striking visual form.
With the free Roambi plan, you can quickly import your Excel or CSV data into the app and pick from four dashboard displays: CataList, PieView, SuperList, and Trends. In the pro version (US$99/user per year via the Google Apps Marketplace) you can add connections to Salesforce CRM and Google Docs for live online updating; the ES3 enterprise version gives access to high-end business intelligence systems from SAP and IBM, along with device-lock security and remote data wipe options to protect your key info. The enterprise version also provides access to Flash/browser versions of the same dashboard displays, in case you need to show your stuff sans iPad.
The graphs and dashboards themselves are a visual treat. You can easily drill down into your data with a few touches, or bring up a trendline or sparkline to make a clear point. If you've got a view you want to return to quickly, you can bookmark it for instant access; you can also easily send screenshots of a particular view.
It's not an app for everyone, but if your day includes explaining numbers to others, you need to give Roambi a shot. It's also available in a free iPhone edition.