DELETE YOUR LAYERS
In earlier versions of Photoshop you could press the Delete key to delete a layer but you had to have the Move tool selected first (weird, I know). Now they've changed it so you can press the Delete key with any tool selected (well, nearly any tool) and it'll delete the currently selected layer for you. The only catch is it doesn't work with tools that the Delete key actually does something with (ie. the Pen tool or the Magnetic Lasso tool).