tick, tick, tick, tick, tick

Newton's Cradle is the archetypal executive toy, found on the desks of doctors, lawyers and businessmen everywhere.

Consisting only of five stainless steel balls suspended by two strings apiece (to prevent lateral movement), Newton's Cradle was originally devised to illustrate conservation of momentum and energy.

Newton's Cradle demonstrates that the momentum of x number of pendulums on one side will be transferred (through one or more seemingly stationary pendulums) to x pendulums on the other side.

--+-+-+-+-+--        --+-+-+-+-+--
/  | | | |            | | | |  \
/   | | | |     -->    | | | |   \
/    | | | |            | | | |    \
@     @ @ @ @            @ @ @ @     @
--+-+-+-+-+--        --+-+-+-+-+--
/ /  | | |            | | |  \ \
/ /   | | |     -->    | | |   \ \
/ /    | | |            | | |    \ \
@ @     @ @ @            @ @ @     @ @
--+-+-+-+-+--        --+-+-+-+-+--
/ / / /  |            |  \ \ \ \
/ / / /   |     -->    |   \ \ \ \
/ / / /    |            |    \ \ \ \
@ @ @ @     @            @     @ @ @ @

A more complicated two-dimensional version of this system, the Lattice Newton's Cradle, consists of five rows of five pendulums.