Slope Annotation (Tip #2097) from Leonid Nemirovsky inserts a block with attributes for marking the slope angle. The block is inserted at the default scale and angle for blocks in the current drawing with the attributes filled in based on user input. This tip is a great example of how you can make custom commands that get the job done quicker. Combining AutoLISP with AutoCAD commands and entities is the best way to improve productivity.