Custom functions are a powerful feature in Google Sheets that allow users to create their own custom formulas. They can be particularly useful in automating repetitive tasks and streamlining data analysis. For example, you can create a custom function to fetch real-time stock prices from an API and populate them in your spreadsheet. Another practical use case is creating a custom function to automatically generate unique IDs for database records when importing data into Google Sheets. The possibilities are endless with custom functions!

Custom functions can be leveraged to enhance collaboration in Google Sheets. Imagine you're working on a project with multiple team members and you want to assign unique tasks to each team member. By creating a custom function, you can generate random task assignments and assign them to specific individuals. This not only saves time but also ensures fairness in task allocation. Additionally, custom functions can be used to perform complex mathematical calculations that are not available as built-in formulas in Google Sheets. So, whether it's automating processes, improving collaboration, or performing advanced calculations, custom functions are an invaluable tool in Google Sheets.