On the high score screen after the games is over (you don't need a high score), type "HEADLIKEAHOLE" and press the 'ENTER' key on the keypad. Use 'F1-F10' to skip levels. This also gives you infinite lives. Hold 'SHIFT' or 'CTRL' and press the function keys to access the other levels.
1-1: Absorb the spider to get some food. Jump to the putties in the window for a score bonus.
1-2: Jump around to find watches.
1-3: Go to the bottom-right of the screen, and jump to receive a score bonus.
2-1: The tree at the top of the level gives you extra score, and the tree at the bottom gives you Dweezil power.
2-2: The first tree gives you a score bonus, and the one above it gives you a pair of false teeth if you jump.
2-3: If you jump on the lowest tree on the right you will receive the bubblegum.
3-1: Mould into a rabbit to kill the Gut Buckets, and turn into an Electro Worm to kill the light bulbs. Jump at the top for extra power ups.
3-2: To get Dweezil power, jump on the picture. Jump near the planet to activate Uncle Ted.
3-3: Jump at the girl's face and the computer screens in order to get an arrow and an elevator.
4-1: Jump at the middle door at the bottom to activate Uncle Ted. At the top of the level, jump at the right gong to get an elevator.
4-2: Jump at the middle door to activate Uncle Ted, and at the dragon symbol for bubblegum. Jump on the door for an elevator.
4-3: Jump on the symbol on the right for an arrow.
5-1: There are plenty of bonuses on this level. The best one to get is the dustbin - to obtain this you have to jump on the cannonballs at the top of the level.
5-2: Some of the igloos have food in them.
5-3: Some of the doors have food in them.
6-1: Jump around to get arrows.
6-2: There are bonuses in the pictures.
6-3: Jump near the tower for a surprise.