Calculating an Aging Column in SharePoint 2007
Here's an interesting problem... with a more interesting solution!
Let's say you want to create an Aging column in your document library (i.e. the number of days since the document was last changed). Since SharePoint supports calculated fields, this should be easy. Right? No. The challenge is using the 'Today' function in a calculated field. When you try to use it, SharePoint throws an error with a reference to Today being a volatile function. How to get around this? Do the following...
1. Create a new column called 'Today'. Make it a single line of text.
2. Create a new calculated field called 'Aging'. Give it a formula of 'DATEDIF([Modified],[Today],"D")'. Have it be a number with 0 decimals.
3. Go to the edit page of the 'Today' column and delete it.
Now look at your Aging column. It worked! It shows the number of days since the document was last modified. Sneaky... but it works!