EyeToy: Monkey Mania (also known as Saru Eye Toy Oosawagi: Wakki Waki Game Tenkomori!! in Japan) is a game that requires the EyeToy camera to play. It is based on Ape Escape and the monkeys in the game are guided through 50 minigames. Up to four players can play together.
The game is available with a silver camera or without for those who may already have the EyeToy.
Source: Wikipedia, "EyeToy: Monkey Mania", available under the CC-BY-SA License.
The Ape Escape series is notable from its radical departure from the tried-and-true control method in most other games. It was the first PlayStation game to require the use of a DualShock controller; the left stick moves the character while the right operates whatever gadget the player has in his/her possession. Again, unlike many games which use PlayStationX.svg to jump, both the R1 and R2 buttons are used, while the 'shape' buttons are used to cycle through the available items in the inventory.
The main objective through the majority of the games is to use your available array of gadgets to locate and capture monkeys. When a monkey has been found, he needs to be caught with the Time Net gadget. On the first through, players will have a set number of monkeys to catch before progressing towards the next level. Once each level has been completed, they can be reentered with the gadgets necessary to catch the remaining monkeys.
Source: Wikipedia, "Ape Escape", available under the CC-BY-SA License.