Multiline TextBox expand as characters exceed space

I want to put a 2 line multiline textbox on the page.

As the user fills up the two lines, I want it to grow another line, etc.; so they still see the entire box as they're typing.
Maybe also have the ability for a maxrows of so much.

Is there anyway to do this?

Using VB and asp.net 3.5 sp1.

thanks.