If you just want to explore the cube yourself you can connect to Analysis Services via SQL Server Management Studio (SSMS) and Browse the cube. Otherwise Excel is very powerful and can be used to connect and explore the cube with PivotChart and PivotTable functionality. If you are looking more for canned reports try Report Builder or SQL Server Reporting Services. If you want dashboards PerformancePoint works well with Cubes. There are many other third party options as well, it just depends on what you are trying to accomplish.