Klondike doubled: two decks, thirteen columns of four, and eight foundations building in alternating colors instead of by suit. Clear a column and it's gone for good.

Bureau Solitaire plays like a doubled-up Klondike: two decks, thirteen tableau columns of four cards each, and eight foundations instead of four. The two rules that actually change the game are these: foundations build up in alternating colors instead of by suit, and an empty tableau column can never be refilled once you clear it.
Athena Solitaire is the solitaire game closest to this one.
You already know the original Solitaire — this is what happens when you double everything about it.
If you run into anything odd or have an idea that would make the game better, please contact me.
Enjoy yourself!
There are eight foundation piles.
Any ace can start an empty foundation pile.
A card can be added to a foundation pile only if it's one rank higher and the opposite color of the pile's current top card, so the only card that fits on a Q of hearts is a K of spades. A pile holds at most 13 cards.
The top card of each foundation can be moved back into play if another pile will accept it.
Thirteen tableau piles of four cards each. The odd-numbered cards in each pile are dealt face-down, and the even-numbered cards are dealt face-up.
A card can be added to a tableau pile only if it's one rank lower and the opposite color of the pile's current top card, so the only card that fits on a 5 of hearts is a 4 of spades.
Cards on the tableau that are not covered by another card can be played onto the foundation or any non-empty tableau pile.
Empty tableau spaces can never be filled.
Alternating-color runs of cards in order from high to low can be moved together from one tableau column to another.
There's one waste pile, and the remaining cards make up the stock.
Clicking the stock deals one card to the waste. You get two passes through the stock.
The top waste card can be played to any non-empty tableau pile or foundation.