I am wishing to add a page to our internal website that will show overdue accounts.

I want to show today's date and then based off today's date show days in advance

ie - Today's date is 2012-04-03

3days: 2012-04-06
7days: 2012-04-10
30days: 2012-05-03
90days: 2012-07-02

I can't figure out how to add days?!?!?!

Any and all help would be greatly appreciated