The Sandler Deck
Some time ago I realized that the problem with the standard 52-card deck is that 52 is only divisible by 2, 4, 13, and 26. This limits the sorts of games you can play- for example, you can't play 6-player bridge, because you can't give each player 8.7 cards. A number of solitaire games involve laying out the entire deck in X stacks of Y cards each, and X and Y have to be 13 and 4, unless you want the stacks to be uneven. I thought a bit about how one might construct an interesting alternative deck and eventually decided on a deck with three colors, and the following nine suits:
Hearts, Diamonds, Suns
Clubs, Spades, Omegas
Stars, Moons, Hammers
The ranks of the cards run from Ace through 9, with the face cards, in order, being Knight, Dragon, and Princess. The deck thus has 108 cards. 108 has a large number of divisors (it is 3*3*3*2*2) and thus can be divided up in a large number of ways, and the addition of a single Joker raises the total to 109, which, being prime, cannot be divided up evenly at all.
Thus far I have not had a chance to actually create a Sandler deck, and therefore haven't had a chance to actually play any games with it. There are a large number of possible ways in which one could modify existing games for use with the deck, particularly since each color has three suits. For example, in Skitgubbe one could have the trump beat other suits of the same color, which in turn would beat suits of other colors. If I ever get a chance to actually experiment with one, I'll write more about the deck here.
The Sandler deck is Copyright 1997 by Ben Sandler.