Keeping the dock visible without affecting window size? Is there any way to keep the dock visible without it affecting the size of windows?

On my MBP 13" I have the dock hidden since it simply takes to much screen real estate, but working with a tablet I feel the need to have it visible at times. And I don't want to hide/unhide with a shortcut, I just want it to show on top of my windows.
Most apps dont allow that. Some, like excel, allow you to resize the window as you like... even if you dont like the shortcut, you can use it to achieve what you are looking for... although its not very convenient.. you can hide the dock, maximize the window and then unhide it.. it will show ontop of the window.