One of my favourite features in Illustrator is that it rounds units to the nearest ten when using shift and clicking the up/down buttons or hitting the up/down keys.

Just to be 100% clear, I’m not talking about bumping up/down by exactly 10px like what Photoshop does. If a shape is 23 pixels wide and you hold shift and hit the up key while the width text box is focused, the shape will bump to 30 pixels, not 33 pixels. It’s glorious!