Letter Jam is a 2-6 player cooperative word game, where players assist each other in composing meaningful words from letters around the table. The trick is holding the letter card so that it's only visible to other players and not to yourself.
By doing so, each player gradually learns what letters they're holding. At the end of the game, by filling in the blanks and rearranging their letter cards, everyone has to find the word hidden within these cards, still without looking at them! In the end, the more players managed to create an existing word, the bigger their common success.