The other evening I was both caffeinated and tired, at the same time. Trying to sit cross-legged left me feeling tense and jittery—not ideal for meditation.
I tried lying down, and everything got easier. Relaxing was almost automatic, I presume because the body associates lying down with sleep and relaxation. And my hands resting on my stomach, rising and falling with every breath, were an easy point of focus. (I've found it a little challenging to focus on my breathing, when sat upright.)
I've heard there are four "dignified" meditation positions: sitting, lying down, walking, and hooking your legs around a beam and then hanging upside down.*
* Not a trained meditation instructor. This list may not be 100% accurate.
The point is, lying down is kosher, as far as meditation goes. I'm not going to do it regularly just yet, but it's a nice option to have.
Does anyone meditate lying down regularly? Let me know in the comments, I'd be interested to hear why.