Another great example is the last post on the keras blog [1] "Using pre-trained word embeddings in a Keras model". You take advantage of a large pre-trained network for a text classification task.

The OpenFace face recognition library also offers this technique. You take advantage of their large pre-trained network for face embedding: transforming a face into features distinct enough for classification. You then train another few layers for recognizing your own samples.

1: https://blog.keras.io/using-pre-trained-word-embeddings-in-a...