One of the cool new features found in Adobe InDesign CS5 is the ability to balance the amount of text appearing in multiple columns.
Take the image above for example. Rather than inserting hard returns, using the Enter key to force text to the next column, or adjusting the size of the text container itself, you can simply use the Balance Columns feature. To do so, select the text container to make it active, then go to Object>Text Frame Options… (or hit Command + B). In the dialog box that appears, tick the Balance Columns checkbox. The results are a balanced columns of text, regardless of the text container size as seen in the image below.
The beauty of this feature is that you can add more text later and the text columns will always adjust to stay balanced, as opposed to having to go back manually and remove hard returns or re-adjust the size of the text container.