Toad balloon

Toad balloons, also referred to as Toad coins, are items that appear in New Super Mario Bros. Wii. They are blue balloons with a picture of a sad Toad's face on each. They appear in Enemy Courses. Mario has to collect all eight balloons in the Enemy Course. Afterwards, a chest appears with a Toad in it and the player wins three Super Mushrooms. Toad balloons appear in every world except World 9, since there are no Enemy Courses in said world.

Trivia

 * Judging from the filename, Toad balloons were intended to be Green Coins.