Utility -- Magic Gnome Collections - The Sims 3 Ambitions
OK it is not so much a collection in the sense that you collect them, but rather a collection of Magic Gnomes that is spread across the base game and expansions.
Gnomes change poses, use objects, clean objects, and just plain moves around your lot when you aren't watching them! The hours of trickery are between 9 PM to 4 AM; the chance of your Gnome executing one of these options runs between 10% and 80% -- and Gnomes that reside on your lot for a length of time may show a preference for specific objects, especially expensive ones (valued at over $1500).
Your Gnome may seem to go dormant for a while - they don't move or do something every night, and as the chances of them doing something are random, you may have to wait a while for your Gnome to move. They have a range of positions that you can find them in, including standing, proud, handstand, dancing (2 poses), scared, pointing, examining, lying Down, sitting, and sleeping.
While some of these are benign, others can range from spooky to outright hostile and dangerous! You have been warned!
Here is the catalog of Gnomes and how they are found/obtained:
Abracadabra (AM) -- 5% chance found in an expensive clothes dryer; desires washers, dryers, clotheslines, clothing piles, and hampers.
Blingaboo (LN) -- May be given as gift to 5-star celebrities; desires hot tubs, bars and expensive cars
Carter Caninenimus (PET) -- 0.7% chance to spawn per Dog best friend.
Cranstan Boonitz the Magic Gnome (ST) -- Unknown spawn conditions
Felix Felinenimus (PET) -- 0.7% chance to spawn every time a cat receives the "Whacked Out" moodlet.
Freezer Bunny Gnome (PET) -- 0.1% chance of spawning every time a dog barks or cat freaks out at the fridge.
Little Léon Magic Gnome (WA) -- found in France; desires nectar racks, fridges, and edible objects.
Lounge Lizard the Magic Gnome (ST) -- This gnome can spawn in the lot has of a Sim with a singing skill of Level 7 or if a Fried Peanut Butter and Banana sandwich is left out.
Magical Gnome of Invention (AM) -- 2.5% chance of gnome instead of a new invention while inventing, or 1.5% while making inventions; desires inventions and invention workbenches.
Magical Gnome of Sculpting (AM) -- a chance this gnome will be sculpted by a level 5 sculptor; desires sculptures and art objects.
Magic Vampire Gnome (LN) -- 15% chance this gnome will spawn if you have 3 plasma fruit bushes in yard... After sunrise this gnome will attempt to move indoors; desires Snuggles WugglesWorth and it can turn a Snuggles WugglesWorth bear into a vampire gnome.
Master Manchu Magic Gnome (WA) -- spawns in China; desires canvas and paintings.
Mysterious Mr. Gnome (TS3) -- may be found while exploring Mausoleum Catacombs, Fishing, and time traveling; desires plants, outside objects, and expensive objects.
Sultan Sam Magic Gnome (WA) -- Found in Egypt; desires Relics and Gems.
Troglodyte (AMB) -- Found while using the Miner or traveling to the past; desires food, outside objects, and plants.
Zenyatta (PET) -- Can spawn whenever a horse licks a salt lick for 80 minutes and the chance increases by 0.2% for every 20 Sim-minutes the horse licks the salt lick.