What is an quick way to create a new blank file in Lion?
A simple drag-and-drop solution works for me.

Create a folder called "New documents". In this folder, save a blank document of each type you want. In my case, I have a blank TextEdit document (.rtf) and a blank TextMate document (.txt).

Lock this folder (select, cmd-I, click 'Locked').

Put the folder in the Dock.

Now, whenever you want a new document, you simply drag it from this Dock folder to wherever you want it. Because the "New documents" folder is locked, the original won't be deleted; rather, the Mac will make a copy for you.