A game for site swapping jugglers. Created after discussions at the mailing list firstname.lastname@example.org. First test at the Erlangen Convention on Nov. 28th 1998. These notes were written on Aug. 8th 2004. The current version of this is found at http://www.jongl.de/siteswap-rummy.html
The players have cards on which are numbers. They build siteswaps and perform them. When the pattern is recognized or juggled for 20 rounds without a drop (whichever happens first), the cards may be put down. The first to have no cards left is the winner.
Material: 2 standard packs without the picture cards (Jacks, Queens, Kings). That is a total of 2 x (52 - 12) = 80 cards. Cards numbered 2, 3, 4, ..., 9 represent siteswap throws of this value. For jugglers below expert level, a 10 represents a 0 and an ace is a 1.
Up to 6 jugglers can play, and a set of up to 10 juggling balls will be needed (although most jugglers will prefer to use their own set).
When 2, 3 or 4 jugglers are playing, everyone starts with 8 cards. 5 players start with 7 each. 6 players start with 6 each. After dealing, the rest of the pack is placed face down. The top card is overturned and placed face up, by the side of the face down pile. The face down pile is called the pick-up pile. The face up pile, consisting of only the 1 card initially, is called the discard pile.
The (youngest) player without a degree in mathematics starts, and then in turn:
Build a siteswap as long as possible (consisting of at least 3  of your cards) and lay down
all of your cards face down, with the siteswap that you are
going to perform at the top, in order (so if you are going to do 534, the top
cards must be 5, then 3, then 4). Therefore no-one can tell how long the period
of the siteswap will be, but everyone can see how many cards the juggler still
has left. The sorting order is important, because 741 and 714 are different
juggling patterns and therefore have to be recognized as such.
Alternatively you may extend an already laid-down siteswap. You may use less than 3 cards for this play. The order of the existing (laid down) cards may not be altered, but new cards may be inserted (for example, 423 may be extended to 451233). Lay down your cards face down, as described above, with the top card being the first number to be added, and so on (so in this example, 5 would be the top card, then 1, then 3).
One final alternative, is to juggle any non-siteswap pattern. When this is guessed correctly, two cards may be placed onto the discard pile, and two cards then taken from the pick-up pile.
Legal are all siteswaps of period (length) 3  or longer, containing at least 2 different values (note: 5151 is valid, as it has period 4 - but guesses of 51, 15, 5151 and 1515 are all classed as correct).
If you want to play a siteswap that has already been played, then the juggling has to be modified, e.g. with clubs instead of balls, with left hand instead of right, in Mills Mess etc.
Perform the pattern until another player recognizes it ,  (Even expert jugglers make mistakes, e.g. Ben Beever tried 9995 with 7 balls. After several tries he recalculated and took another ball. "Much easier", he said.)
When your pattern has been recognised, reveal the siteswap by turning the cards that you used face up, from the top of your pile (unless you played a non-siteswap, in which case just exchange 2 cards).
The juggler who recognized the pattern is allowed to change 1 card. He may pick a card either from the pick-up pile, or the discard pile. He then places one of his cards onto the discard pile, face up.
If no-one recognizes your pattern (a few hints are allowed), you are unlucky, and are not allowed to lay down your cards. However, if you are able to show your pattern for 20 cycles without a drop, and still no-one recognizes it, you may stop and lay down your pattern anyway.
At the end of your turn (even if you chose to skip your turn), you must take one  new card from the pick-up pile (you now have time to think about your next pattern), unless you added cards to an existing pattern, in which case you don't take any new cards.
If you have fewer than 3 cards, you may, at any time, take another card from the pick-up pile.
The turn then passes to the player on the left.
The winner is the first to get rid of all his cards.
If the pick-up pile is ever exhausted, the discard pile is turned over to become the new pick-up pile, and the top card is turned over to start a new discard pile.
If extra cards are added to an existing pattern, the new pattern must be a valid siteswap before any value reduction. For example, if a novice has played 915 as 612, no-one can add a 3 to make 6312, as the period of the pattern is now 4 (so the 9 must be reduced to a 5), but someone could add a 5 to make 9155 (which could be juggled as 5155 if this player hasn't flashed 9 before, or even 5111 if they haven't flashed 5 before).
 Extension of May 29th 2003: No tried yet, but as a
proposal: The juggler must do as many catches as the highest number in the
pattern (or three times the period or 10 throws with the right hand). The
motivation for this proposal is that you will recognize e.g. 80 immediately,
even if the juggler is no-where near being able to do it.
 Advanced Players Extension (July 31st 2004): After each round players draw 2 cards instead of 1 (unless they insert cards into an existing pattern, in which case they still don't need to pick up any). (Period-2-patterns are then allowed because the number of cards held is not being reduced by this play) This extension increases the length of a game, and is recommended if all players are able to build and juggle siteswaps with long periods.
 Punishment for guessing wildly: Everyone who has two or more wrong guesses has to draw a card after each wrong guess.