Pivot tables are an amazing feature that not many people fully utilize. They give you the ability to summarize and analyze large data sets with just a few clicks, providing valuable insights.

Another powerful feature is Excel's array formulas. They enable you to perform complex calculations on multiple cells at once, saving time and effort compared to traditional formulas.

Excel's 'Get & Transform' (formerly Power Query) feature includes an option to merge queries, which allows you to combine multiple data sources into a single table. It's excellent for consolidating data from different systems into a unified view.

Excel's 'What If' analysis tools, such as Goal Seek and Scenario Manager, are incredibly useful for performing sensitivity analysis and exploring different scenarios to understand the impact on outcomes.

I love using Excel's conditional formatting feature. It allows me to visually highlight certain cells based on specific conditions, making it easier to spot trends, outliers, or discrepancies in my data.

Excel's Power Pivot and Power BI integration is a game-changer for creating interactive and visually appealing dashboards. It enables seamless data modeling and analysis across multiple sources.

One feature that I find incredibly helpful is Power Query. It allows you to easily connect and transform data from various sources, making data cleaning and analysis a breeze.

One of my favorite lesser-known features is the 'Trace Dependents' and 'Trace Precedents' functionality. It helps you understand the linkages between cells and formulas, making troubleshooting and auditing your spreadsheets much easier.

Data validation is often overlooked but very useful. It allows you to set restrictions and rules on the type of data that can be entered into a cell, ensuring data integrity and accuracy.

Solver is an advanced tool that allows you to optimize and find the best solution to complex problems. It's handy for tasks such as resource allocation, production planning, or financial modeling.