For fun I put together a small script that is capable of introspecting databases and generating peewee models. I borrowed the crucial bits from django's codebase, which has methods for introspecting column types and foreign key constraints.
The code is hopefully rather straightforward - it simply grabs the list of tables, column type information which is then mapped to peewee field types, then finally resolves foreign keys. The generated models are then dumped to standard out, along with a database declaration.
After two years of maintaining djangosnippets.org, I am pleased to announce that the guys from django-de are going to be taking over and you can expect to see some real improvements.