Mudras are yoga poses for the hands. Mandala mudra is often used for meditation. You can also do this for about 1/2 a minute at your computer - rest your eyes, rest your hands and take a break.
Take a deep breath, and try this now: left hand turned palm up, right rests in left, also palm up, thumbs touch. This mudra is great for settling you into meditation, helps you feel the connectedness of everything.