The Estonian droodle database, found at www.folklore.ee/folklore contains a compilation of Estonian droodles and their variants. These picture-riddles are fun and sometimes clever. An explanation of them can be found in the database's preface - however, they are, in short, small framed pictures that seems meaningless until the "answer" to the droodle is revealed.
For example, one droodle consists of a rectangle with five circles drawn in it - four form the shape of a square and one tops the square. The answer to the droodle is "an elephant in a swimming pool."
A Fisherman Walking Past a Window
Some droodles may be obvious; others are not politically correct (so be careful before you show images from the droodle database to children). However, a quick perusal is sure to entertain.