To the right, to the right

Late-night TV hosts have their desks placed on the right because it makes them seem powerful:

In Western culture, we read from left to right, and we watch theater and television that way, too. Our eyes end up on the right side of the screen -- where the host sits (also known as stage left). In the theory of stagecraft, it's understood that a rightward placement telegraphs royalty. So no matter how famous the guest may be, sitting to the left makes him or her seem subservient. Late-night hosts also sit slightly upstage (farther back and slightly elevated) from their guests, which likewise reinforces the notion of a power imbalance.

It all started with Steve Allen, host of The Tonight Show from 1954 to 1957. Actually, hosts who have strayed from this format (Dick Cavett, Carson Daly, and more recently Jay Leno) have not survived in the studio that long.