SQLObject is an object-relational mapper, i.e., a library that will wrap your database tables in Python classes and your rows in Python instances. It currently supports MySQL through the 'MySQLdb' package, PostgreSQL through the 'psycopg' package, SQLite, Firebird, MaxDB (SAP DB), MS SQL, and Sybase. It should support Python versions back to 2.4.
Python bsddb3 is a Python module that provides a nearly complete wrapping of the Oracle/Sleepycat C API for the database environment, database, cursor, sequence, and transaction objects, and each of these is exposed as a Python type in the bsddb3.db module. The database objects can use various access methods: btree, hash, recno, and queue. It has complete support for Berkeley DB distributed transactions, and complete support for the Berkeley DB Replication Manager and base replication API. The goal is to mirror most of the real Berkeley DB API.
pyratemp is probably (one of) the smallest complete template-engines for Python (with about 500 LOC). It has a very small set of special syntax in the templates. This reduces complexity and the probability of bugs and lead to an easy-to-use and intuitive user-interface. It uses embedded Python-expressions (in a "sandbox"), is well documented, has full Unicode-support, and produces very good error-messages, which is very useful when creating new templates.
pacparser is a library to parse proxy auto-config (PAC) files. Proxy auto-config files are a vastly used proxy configuration method these days. Web browsers can use a PAC file to determine which proxy server to use or whether to go direct for a given URL. The idea behind pacparser is to make it easy to add PAC file parsing capability to any program (C and Python are supported right now). It comes as a shared C library and a Python module that can be used to make any C or Python program PAC scripts intelligent. Some very useful targets could be popular Web software like wget, curl, and python-urllib.