World of Trinketz is a family-friendly MMO that you can play in your browser on Facebook. In the game, you take care of everyday objects that have come to life which are known as Trinketz. If you treat them well and take good care of them, they'll become your friends and reward you with items that you can use for crafting or as currency. Trinketz come in three distinct flavors, Normy, Sugary, Scaley and Clanky, and as they level up, they unlock customization options such as new textures and "flair" meshes that you can use to personalize your collection.
In addition to all of that, players can also expand and customize their home world with landscape pieces or "habitats" to further customize their experience. Habitats also provide daily rewards when they have complete collections of trinketz. For example: a beach habitat will give a daily gift box when it has a tropical tree, beach lounger and umbrella trinketz placed on it.
There are also large public spaces that players can explore. There, they'll find NPCs with quests they can undertake. Play minigames to collect resources for crafting and taking care of their trinketz. Adoption centers where they can find new trinketz as well as markets where they can buy and sell items. And of course, other players with whom they can chat, trade and share their experiences.
All of this is free to play right in your browser on Facebook. It's a fully 3D game, so all you'll need is the Unity3D plugin installed to your browser. If you don't already have that, the game will provide it to you. It is also free.