CheckMATE is a checkbook manger that lets you make spending categories (virtual envelopes) for your checking account! You can see screen shots of its features in the Help section on this site.
You enter your deposits, set up any spending categories you like and then transfer money to the categories as you wish! When you write a check, you tell CheckMate which category to take the money from.
One simple report tells you how much money you have available to spend in all of your categories.
It will be available for purchase as a download soon.