Anyone who reads my tips and newsletters knows one of my favorite Outlook features is date shortcuts and natural language capabilities. Most date fields accept shortcuts or phrases (like a "week before Christmas") and converts to the proper date.

Another of my favorite features is Filters (used with Advanced find, Search folders, Automatic formatting and Views). The Advanced tab on the filter dialog gives you many filtering options and you can use natural language tricks with them. Filtering has a few idiosyncrasies, like the From field on the General tab is not the same as the From field on the advanced tab and OR operator is not supported. But otherwise, it's full of potential and you can use some of the natural language tricks with it.

I was reminded of this when a person asked how to create a search folder for all messages older than 45 days. Using dynamic dates, so it shows items older than 45 days next week or next month.

Easy: use "ago" as in "Received on or before 45 days ago". This should always return the correct set of messages and changes daily.