My company is called ProfitFromERP. We help people select and implement ERP solutions. I don't personally use Hyperion day to day, but have clients who've selected and grown with the program. Hyperion historically has been a high-end tool for financial planning and analysis groups who want to create things like forecasting models and work with real-time data and events in-progress to update rolling forecasts.
Hyperion is useful for advanced financials, reconciliations, and other things that traditional accounting and reporting solutions don't do. Some people use it for their SEC reporting and things like that. Others are trying to compile data from multiple sources - various databases and transactional systems.
For example, we've got hockey teams that cross-reference ticket data and information from third-party concession stands to get a complete picture of what's happening in their entire stadium. It provides them with real-time information from point of sale systems, Ticketmaster, and gate scanning systems, all so they can optimize staffing in every section and maximize revenues by having the right staff in the right place.