British Airways have square ones with horrible, itchy covers. Virgin Atlantic's are smaller, or rather, rectangular, and have the same fabric covers. I think these covers are only used once and thrown away. Singapore Airlines' pillows are, in my experience, the nicest; plump with silky smooth covers (made of cotton?)

Which airline has the best pillows? (specifically in economy/ premium economy).

Edited to add: Hmmm...guess this is a crap topic then.