When Willy Wonka sang about “A World of Pure Imagination,” he might as well have meant “LittleBigPlanet.”

This platformer from Media Molecule not only presents players with one of the more aesthetically inspired games in recent memory, it allows those players to mold their own additions to the game's landscape.

Its titled sphere is populated by Sackboys and Sackgirls, burlap mascots whom players can dress up dozens of ways: as zombies, brides and grooms, luchadors, Elizabethan English citizens and more. Players can adjust the adorable protagonists' faces - from frowning to frothing mad - and animate them with tilts and twists of the PlayStation 3's Sixaxis controller.

Players must maneuver those anthropomorphic fabrics through terrain teeming with all the usual platform hazards: fire, water, spikes and bottomless chasms. Like Mario, Kirby, Klonoa or any platform navigator, Sackboy can avoid these perils by running and jumping. A grab command also allows Sackboy to move blocks or ramps to help him reach great heights, clutch dangling ropes to swing over dangerous ground and drop bombs on breakable surfaces.

But “LittleBigPlanet's” delicate physics distances it from the majority of platform titles. Sackboy cannot simply move at the same speed all the time. With each landing on a surface, his momentum shifts. It's subject to the amount of speed he accumulated before jumping and the angle at which he lands. If Sackboy walks from one end to the other atop a fabric block, it remains fully grounded. But if he runs, the block starts to tip due to the build in momentum.

When surfaces move as well, such as a teeter-totter, a cruising skateboard or that same fabric block, players relinquish slightly more control of Sackboy to the forces of physics. Their impact upon “LittleBigPlanet” is neither deep nor discouraging, but their influence demands attention from players accustomed to sturdier platform mechanics.

“LittleBigPlanet” also enriches the platform formula by adding up to three horizontal planes to its sidescrolling perspective. Navigating levels often necessitates a switch from one plane to another, though doing so in some situations can send Sackboy plummeting into a pit of flaming charcoal or any other hazard. Players who want to claim every Sackboy accouterment, sticker and other goody must explore every plane to reach each level's hidden pockets.

The fresh platform play dynamic of “LittleBigPlanet” is presented in one of the most charming graphic packages in video game history. Its homemade look lends the impression that the levels were hand-crafted by children with cardboard, markers, fabric, stickers and any other decorative tool they could find. Waves of water are cut-out cardboard wrapped in blue denim, castles are cardboard scrawled with black pen and a makeshift south-of-the-border jail is guarded entirely by green toy soldiers.

The massive imagination Media Molecule poured into the game's levels infuses them with a youthful, almost dreamlike atmosphere captured by the best “Super Mario” games. And as much trouble as one song selection caused Media Molecule (the game was delayed a week to remove a song revealed at the 11th hour to contain Quran verses), the surviving music sustains the game's carefree climate with buoyant rhythms and infectious hooks.

Playing the levels Media Molecule designed comprises less than half of “LittleBigPlanet's” lasting appeal. Players with an Internet connection can indefinitely extend their time with the game through its level creation features. An editor with full customizing power lets players shape their own landscape of hazards and vibrant infrastructure, then publish it for others to peruse.

Though Media Molecule has yet to deliver players a reliable way to distinguish the skillfully designed levels from the dull ones, the former are not too hard to find. The online component of “LittleBigPlanet” also permits players to post on message boards for each level, rate them and co-op through them to swipe goodies only obtainable with a partner.

After several hours navigating the game's worlds and learning to shape my own, my thumbs still tingle with the sensation of not yet having scratched “LittleBigPlanet's” surface. Any attempt to sum up the game's purpose for the uninitiated feels inadequate and almost ignorant of the massive potential lying within. As homemade levels like a ship-for-ship recreation of the first level of “Gradius” pop up on the “LittleBigPlanet” servers, our grasp of that potential ever so slightly tightens. It's truly a “LittleBigPlanet,” we just play in it.