Pogo Stick

From SuperTux

The Pogo Stick will give Tux the ability jump higher and to break blocks when he jumps on them. This will work simular to the NES game Ducktales and the PC game Commander Keen.

Perhaps this should be just like a star, just a temporal ability. To avoid making the game too easy. It could also be like the boot in Super Mario Bros. 3, which allows the player to jump on usually harmful enemies, but is gone a the end of the level.