I'm looking for a flexibly way to allow a user to input a a field, but also to have that field be a node node reference if the the node reference already exists. In other words, lets say I have a content type called dog, each dog has a node reference for favorite toy, if the toy exists, this field should be a node reference, otherwise the user should be allowed to fill it in. Conceptually I can think of two way to do this. One way, is just to make it a field, and then somehow link to another node if it exists. The other is to make it a node reference, and perhaps somehow auto - create the node when the user fills it in.
Recommendations? (using drupal 7)