Microsoft Excel is one of the most famous applications for a reason.
With the simplest structure of a spreadsheet, you can design your own table, chart, database—yes, you CAN design a complete database inside Excel—along with programs and tools which you can control. With said programs, (aka Macros or VBA code) you can decide how they will behave using all the features inside Excel, such as sorting, Autofilter, PivotTables, and the most valuable feature, functions. And many many more!
There is an incomparable power in Excel. With any tool imaginable at your fingertips, there is no limit to what you can create. Whether it be the most advanced programs or simply making schedules, Excel offers you the opportunity to manage, design, build, and systemize the world around you.
In a sheet, you can zoom out, change the width of all 65k columns (or 256 columns in Excel 2003 and earlier) and color the cells in to create art, which is what this guy did
Or you can have your macros running automatically on a machine based on a certain schedule (using this free tool). This creates periodic reports and charts from changes that happen in a database then sends these reports as emails to higher management. Which is what this guy did.
Or use it to organize your often hectic obligations. For example Excel can help you control your financial undertakings by logging your past bill payments, which in turn displays the number of days left to pay future bills.
Or log your vehicle fixes and maintenance to remind you of future scheduled maintenances.
Or even use it as a print-out calendar using templates
Some took it even further! For instance, this guy who created an Excel tool to create bootstrap websites using the user settings from Excel sheet.
Others create complete systems and tools that run on user interaction or just a single click.
The bottom line is this: creating applications in Excel is the fastest way to do get the job done in a practical, quick, and effortless way, freeing you of the tedious routines that occupy our minds and take away from what truly matters.
And the good news is you can do it, easily. And yet, it is getting easier.