Vasisthasana (Side Plank Pose)
Most of us will simply know this pose as Inclined Plank pose. This asana has a lot of strength and balance, which is no surprise 
if we look at the heritage of the word Vasistha. In Hindu mythology Vasistha was the chief of seven venerated sages and the rajaguru of the Solar Dynasty. He was famous for subduing the armies of the Viswamitra; and he had possession of the divine cow Nandini, who was able to grant anything to her owner. Now you may not get anything you want by practicing Vasisthasana, but you will help your body, mind and spirit.
Vasisthasana is a sixth chakra pose.
Yoga Journal offers a step by step guide on practicing this pose. 
Benefits include:
Strengthens the arms, belly, and legs
Stretches and strengthens the wrists
Stretches the backs of the legs (in the full version described below)
Improves sense of balance
The full version of Vasisthasana, as taught by BKS Iyengar, with the top leg raised perpendicular to the floor, is beyond the capacity of most beginners. The pose described here is a modified version suitable for all levels of students.
(vah-sish-TAHS-anna)
Vasistha = literally means “most excellent, best, richest.” Vasistha is the name of several well-known sages in the yoga tradition. There’s a Vasistha numbered among the seven (sometimes 10 or 12) seers (rishis) or lords of creation (prajapatis), and a Vasistha who’s author of a number of Vedic hymns. He’s also said to be the owner of the fabulous “cow of plenty,” Nandini (“delight”), which grants his every wish and accounts for his infinite wealth.
Step by Step
Perform Adho Mukha Svanasana . Shift onto the outside edge of your left foot, and stack your right foot on top of the left. Now swing your right hand onto your right hip, turn your torso to the right as you do, and support the weight of your body on the outer left foot and left hand.
Make sure that the supporting hand isn’t directly below its shoulder; position the hand slightly in front of its shoulder, so the supporting arm is angled a bit relative to the floor. Straighten the arm by firming the triceps muscle, and press the base of the index finger firmly against the floor.
Firm the scapulas and sacrum against the back torso. Strengthen the thighs, and press through the heels toward the floor. Align your entire body into one long diagonal line from the heels to the crown.
If you'd like you can stretch the top arm toward the ceiling, parallel to the line of the shoulders. Keep the head in a neutral position, or turn it to gaze up at the top hand.
Stay in this position for 15 to 30 seconds. Come back to Adho Mukha Svanasana, take a few breaths, and repeat to the right side for the same length of time. Then return to Adho Mukha Svanasana for a few more breaths, and finally release into Balasana .
