A simple interface that would allow you to set a variable with a date based on such things as today, yesterday, today - #days, day of week, day of month, etc.
I was thinking of something similar also, perhaps allow simple date based calculations - something like DATEADD in SQL where you can add or subtract days, weeks, months etc.
It would be nice to be able to "force a type" when using a "set variable" action to a date/time - even if it internally just did validation for various date/time formats and still held it as a variant...
TJ