Feep (or FEEP) is an 'Easter egg' type of hidden feature found on MUCKs. When accessed, it allows the user to play the mini-game associated with that particular command. To exit Feep, the user types 'quit'. The term comes from the species of Fuzzball's mascots. According to Fuzzball Software's site on Trebuchet, Feep is a nickname of "Feeping Creature" (which comes from "Creeping Featurism"), and refers to any extra, but useless, addition to a program.
 Mail Feep
When in the mailbox (command 'mail'), typing 'feep' (or any abbreviation of it, such as 'fee', 'fe', or 'f') accesses the MasterFEEP challenge, a game similar in nature to the Mastermind board game. The game is administered by a lynx. The following text is presented:
You reach out for a FEEP and just as you almost have it, an old lynx steps in your way and says, "Halt! I am the keeper of the feep. You may not pass here!" He mumbles some things and then continues, "Oh yeah, You may not pass here without a challenge! You must pass the challenge of MasterFEEP!" He sets out a game board with 12 lines of holes on it, and a hidden area. He explains, "To see the FEEP, you must guess my five colors. Every time you guess, I will tell you if you have a correct color, a correct color in the wrong place, or the wrong color, but I won't tell you wich ones are which! Each guess must be made on a seperate row on the board. If you run out of room.." He chuckles a little, sending shivers up your spine, "Well.. Don't run out of room. If however you are a coward, you may at any time 'quit'. So, on with the challenge!" The keeper rummages around, then announces, "I have made my selection! Now it is your turn.. Guess!" He hands you a small box, and surveying its contents you find colored pegs, 6 colors - Red, yellow, green, blue, white, and black.
If the player wins, the following is returned, which refers to the appearance of the Feep species:
The keeper stands up suddenly and exclaims, "Impossible! Nobody can defeat the keeper of the FEEP!" He searches for words, then just motions you to follow him. Weakly he says, "You must tell none of what you see here." He leads you into the cave of the FEEP, and shows you a ball of fluff with adhesive feet, glued on eyes, a elastic wristband, and a little tag that reads FEEP.
Typing 'quit' triggers: The keeper shakes his fist at you and yells, "Coward!"
 Page #Feep
Typing 'page #feep' or 'p #feep' accesses the number guessing game.
Welcome to page #feep! I'm thinking of a number between 1 and 1024. Try to guess it! To play, just enter numbers, and I'll tell you higher or lower. To quit at any time, type any non number like 'quit' or 'end'. Enjoy!
Typing 'quit' triggers: Quitting the page #feep game! Bye!
 Spoof #Feep
Typing 'spoof #feep' triggers: "Spoof #feep: beep"