So, you have a humongous place, and you have nothing to do with it. You're thinking of a specific function, but have no idea if you can do it or not. In both cases, you are in luck! This is a list of all Contraptions and Contrivances found by Trex.1) 2)
If you have absolutely no idea how to use the following contraptions and contrivances, please see this helpful guide.
Also, you might be interested in knowing that -- right now -- the chance of finding an item is programmed to be exactly the same for each item. Apparent differences are due to statistical fluctuations (and perhaps flaws in the randomness of the random number generator). This may change in the future.
The Robots have set up a Scrapyard Market that will let you sell the items you don't want for Scrapyard Points, and buy the items you do want.
A Contrivance that checks whether someone is Human.
A Contrivance that checks whether someone is a Joker.
A Contrivance that checks whether someone is a Kittymorph.
A Contrivance that checks whether someone is a Midget.
A Contrivance that checks whether someone is a Mutant.
A Contrivance that checks whether someone is a Robot.
A Contrivance that checks whether someone is a Zombie.
A Contrivance that checks whether someone is Male.
A Contrivance that checks whether someone is Female.
A Contrivance that passes if the player has fewer than a specified number of Drive Kills.
A Contrivance that passes if the player's Drive Kills exactly match a specified number.
A Contrivance that passes if the player has more than a specified number of Drive Kills.
A Contrivance that passes when a player types the specified word or phrase as a Commentary Command.
A Contrivance that passes when a player types a Commentary Command containing the specified word or phrase.
A Contrivance that passes if a specified Memory is less than a specified value.
A Contrivance that passes if a specified Memory is greater than a specified value.
A Contrivance that passes if a specified Memory is equal to a specified value.
A Contrivance that passes if a specified digit inside a specified Memory is greater than a specified value.
A Contrivance that passes if a specified digit inside a specified Memory is less than a specified value.
A Contrivance that passes if a specified digit inside a specified Memory is equal to a specified value.
A Contrivance that passes if a player has a particular Memento.
A Contrivance that passes if a player does not have a particular Memento.
A Contrivance that doesn't check anything, and just tells the program to proceed to the next row.
A Contrivance that passes if the last Room the player visited before this one matches the Room specified.
A Contrivance that checks if someone is a member of a particular Clan.
A Contrivance that passes if a random number is more than specified.
A Contrivance that checks against the game's current weather conditions.
A Contrivance that passes if the current Game Time is between two specified values.
A Contraption that lightens the background of the page (for example, in bright sunlight).
A Contraption that dims the background of the page (for example, during dawn and dusk).
A Contraption that darkens the background of the page (for example, at night).
A Contraption that adds tree shadows to the background of the page (for example, in the Jungle or Kittania during bright sunlight).
For best results, use in conjunction with the 'Page Lighter' Contraption.
Don't use this with a Contraption that darkens the page background, it won't look good at all.
A Contraption that adds raindrop graphics to the page.
A Contraption that adds more raindrop graphics to the page.
A Contraption that clears all chat entries in the Story channel for the current Room.
A Contraption that clears all chat entries in the Banter channel for the current Room.
A Contraption that sets a specified Memory to a specified value.
A Contraption that increments a specified Memory by a specified value.
A Contraption that warps a player to a specified Room.
A Contraption that hides the current Room Description.
A Contraption that adds a link to a Page.
A Contraption that blocks a link to a Page.
A Contraption that shows the contents of a Page.
A Contraption the locks a Door that would otherwise be unlocked.
A Contraption that unlocks a Door that would otherwise be locked.
A Contraption that shows a Door that you've previously set to be Hidden.
A Contraption that hides a Door that would otherwise be shown.
A Contraption that takes a Memento from the player and puts it in the Place's Inventory.
A Contraption that dispenses a Memento from the Place's Inventory.
A Contraption that turns on Debug mode even for people without Programming Keys.
Note that if you want to see the workings of the whole program, this should be all on its own on the top row of the Logic Grid.

A Contraption that immediately stops all Programs from running.
With the advent of the Flow Control Knob, the Contrivances which checked for the lack of something were rendered obsolete and removed from the ScrapYard. However, they still needed to be kept around so the programs which use them don't break. Feel free to catalog them below.