Lasso and jQuery
Lasso 8 or 9
Free
Open Source
FAST
Easy clean code
In the demo, as you tab from field to field, it is validated. If the address is correct or found with a partial match, you are able to use the address returned by USPS to populate the remainder of the address section of your form.

It works very well and amazingly fast. They love the way that only parts of the address need be entered to get a correctly formatted address to ensure that what is on record is accurate and deliverable. Very clean and easy to follow code.

Thanks for turning this out so quickly. It works far better than anticipated and does exactly what we need!