An "Elfchen" is similar to a Haiku in that it has a set form, however it is unique in that it has 11 words, the lines having 1-2-3-4-1 words, respectively.  Here’s one I wrote for my student’s Valentine’s Day (Valentinstag!) lesson last night:

Liebe

bewegsam

grosse Gefuehle

veraendert das Herz

bringt uns neue Gedanken

innerlich

2-14-12