Perpetual Motion is a Patience game which has the objective of discarding playing cards from the tableau.
The name Perpetual Motion is also the alternative name of another card solitaire game called Rondo or Eight-Day Clock.
After that, four cards are again dealt from the stock (even if one pile is empty) and plays already mentioned are made.
An alternate way to play, as suggested by Peter Drake in his book Data Structures and Algorithms in Java, gives players easier options for discarding cards.
Various people have used computer programs to play large numbers of randomized games of Perpetual Motion in order to analyze the outcomes.