Billiard table manufacturers have produced convertible billiard tables (in the broad sense) that double as dining tables or as table tennis, foosball, or air hockey, tables, with removable hard tops. Home pool tables, which often lack a ball-return system, are commonly either 4 × 8 ft or 3.5 × 7 ft models, a medium between 3 × 6 ft. bar/pub tables and 4.5 × 9 ft tournament-size models. Low-end tables tend toward the smaller range, and may have MDF or wood beds as an alternative to slate; those with light-weight beds may be foldable for storage, as with table tennis. Miniature tables
Billiard ball juggling disciplines have often overlapped since their successful combination by pioneers like Paul Vandy. An urban legend received cultural attention to many saying, "If the Earth were the size of a billiard ball, it would be smoother". It was used in 2008's Discover Magazine, but mistook the diameter tolerance for smoothness. If the Earth were reduced to the size of a billiard ball, much of it, excluding the Himalayas and Mariana Trench, would be smoother. (see also: Earth's Shape) The phrase "as smooth as a billiard ball" is sometimes applied to describe a bald person, and the term "cue ball"