You can use this function to create a simple bar for values in multiple cells.  Here is a short video on YouTube:

At work I use pivot tables nearly every day. My work does not involve analyzing business or financial data and still I find pivot tables very useful in manipulating data sets, performing on-the-fly calculations, and preparing final reports.

So, what is a pivot table?

A pivot table is a data summarization tool found in data visualization programs such as spreadsheets (e.g. Microsoft Excel). Among other functions, they can automatically sort, count, and total the data stored in one table or spreadsheet and create a second table displaying the summarized data. Pivot tables are also useful for quickly creating cross tabs. The user sets up and changes the summary’s structure by dragging and dropping fields graphically. This “rotation” or pivoting of the summary table gives the concept its name. The term “pivot table” is a generic phrase used by multiple vendors. However, the specific form PivotTable is a trademark of Microsoft Corporation^[1]. – Pivot Table wikipedia entry

See the ExcelBlog.net In-Depth page for more information on Pivot Tables.

Want more rows, more columns?
Think Excel is too small; Only 65,536 rows and 256 columns?

Try the Spreadsheet control; a Microsoft ActiveX control.

Source – Office Tips and Hints Blog

Summary: When you use the AutoFilter capabilities of Excel (Data | Filter | AutoFilter), small drop-down arrows appear at the top of each column in your data table. The color of the drop-down arrows changes from black to navy blue if a filter is applied to the column. The color of the arrows cannot be changed, but there are workarounds that can be used to make filtered columns stand out better. (This tip works with Microsoft Excel 97, Excel 2000, Excel 2002, and Excel 2003.)

Source: Changing AutoFilter Drop-Down Arrow Colors