Project Gemini (SQL Server PowerPivot for Excel)

Microsoft unveiled 'Project Gemini,' later released as SQL Server PowerPivot for Excel. This add-in brought a powerful, in-memory data analysis engine (VertiPaq) and a tabular data model to Excel, allowing users to handle millions of rows and create complex data models with the DAX language.

Significance

This was the foundational technology for Power BI, proving that sophisticated data analysis could be brought directly to the familiar Excel environment, significantly expanding what business users could accomplish.