A game for a small number of players (4-8) and occasionally very large fines.
Tøppen (I'll call it that for now, since there is some debate over the actual spelling) is played either with cards specific to it, or with a shortened deck. It's most distinguishing feature is the card value order with a normal deck: starting at the top the order is 10, 9, 8, 7, ace, king, queen, jack, 6, 5, 4, 3, 2. Normally eight cards more than the number required by the players are in the pack that is dealt (the non-dealt cards being called the drittsekk), and the other cards are put aside; there are no jokers. If many players are participating, a drittsekk of 4 may be used (it has been suggested that the drittsekk should be reduced to four before sixes are introduced into play).
The aim of tøppen is to win the last hand. Each player is dealt four cards, two at a time. At this point, if a player feels that he has no chance of winning, he may fold ab initio by placing his cards face down on the table, and drink a single fine.
The player first dealt to then leads a card, played immediately in front of him. The remaining players, in order, must then follow suit, and also play their cards in front of themselves. The player who has played the highest valued card of the led suit (according to the card value order mentioned above) gets to lead the next hand.
Whenever a player is going to play, he may choose to "knock" (by rapping his knuckles on the table). The other players are then each given an opportunity to fold (in which case their remaining cards are placed face down on the table and a fine is imbibed), or to indicate that they wish to stay in by saying "pah". The "current" fine is then increased by one. Low numbered cards are often used as a die to keep count of the current fine; a player going out due to folding or losing the final hand is then required to drink the number of fining units shown on the die. Note that the die starts at one - folding on the first knock and folding ab initio are equivalent. Note that if all but the knocking player fold, the knocking player wins and does not have to show any unplayed cards. Hence knocking is both a means of increasing the fine for your opponents (assuming you win - you drink more if you lose) and a means of bluffing.
If a player knocks more than once with no other player knocking in between, the potential fine for that player (only) is doubled, in addition to a normal increment. You can't knock twice without playing in between. Hence if a player is the only player to have knocked, and knocks twice, the fine is three for everyone else, but six for that player. Further knocks not interrupted by a knock from someone else produce further doubling - a third knock would give a fine of four for everyone else, and sixteen (a pint, assuming pencil fines) for the knocker. Note that if there are eight players, all of whom knock (so the fine is nine), the last player knocks every hand, wins the second from last hand (and so goes first in the last hand), and all the other players choose to knock again, then if no-one folds the player who multiple-knocked has a potential (8+4+7)x8 = 8.5 pint fine (on pencils) if he loses. Even less extreme circumstances can produce very high fines, and a six pint fine has I believe been seen in reality. Two pint fines are relatively common.
As a historical note, tøppen is traditionally played on finger fines (and was started on finger fines), but general practice involves pencil fines.
Given that, a word of warning for the frisky: while there are unbeatable hands, bear in mind that if you're not leading, many good cards may not be played. For example, if you have the tens of diamonds, spades and hearts and the nine of clubs, someone with the ten of clubs can win the first hand. If he then wins with the seven of clubs (you throw away, arbitrarily, the spade), the seven of spades (you throw away the heart) and the seven of hearts (your last card is a diamond) then it can all go horribly wrong. That said, knocking when you're not leading is not necessarily something done at risk if you see your opponents failing to follow a suit, and knocking as a bluff in the last hand can be particularly effective. Note that a very low last card can win if no-one else can follow suit.
After a hand has been played, the deal passes to the winning player.