Originally Posted by jlofgren
I totally agree. I am looking for a way to do this exact same thing. All of the data input fields are already there. This seems like it would be a really easy thing to impliment.
It might be an easy thing to implement, but the actual implementation of a feature is often a pretty small portion of the whole effort required. You have to test and debug it, document it, support it. There are no free software features :-)
One thing you can do for greater searching and sorting ability for completed tasks is to export them to a spreadsheet. Make yourself a context view, ungrouped, completed actions, that shows all of the relevant actions you want to search. Now do File->Export... and select Comma Separated Values (CSV) as the output file format. Tack .CSV on to the filename, and you should be able to open in OpenOffice, Excel, etc. where you can sort on the Completion Date column and look at the range that interests you. With a bit more fiddling, you could then save the desired rows out as a tab delimited text file and import into OmniOutliner for additional styling.
Or, thinking completely out of the box, install Quicksilver, turn on the text manipulation actions, and use the "." command to add a quick description of whatever you do to a plain text file as you do it. Toss that into OmniOutliner for beautification.