db4o is an object database for Java and all .NET environments. Its features include ACID transactions, automatic class schema recognition, query-by-example, a S.O.D.A. object querying API, native queries, LINQ support on .NET, callback methods, memory files, cascade-on-delete, multi-threaded access, and Java Webstart and servlet support.
Berkeley DB (libdb) is a programmatic toolkit that provides embedded database support for both traditional and client/server applications. It includes b+tree, queue, extended linear hashing, fixed, and variable-length record access methods, transactions, locking, logging, shared memory caching, database recovery, and replication for highly available systems. DB supports C, C++, C#, Java, PHP, and Perl APIs. It supports key-value pair (NoSQL), SQL, and Java Object formatted data. It is available for a wide variety of Unix platforms as well as QNX, Android, Mac OS X, and several varieties of Windows.
Zyan Drench is a simple yet very entertaining game developed using the Zyan Communication Framework. The Game board is a random picture of size 15x15. Start from the top-left corner of the board. Select a new color for the top-left pixel, and all adjacent pixels of the same color will be painted over with the new color. The goal is to drench the whole board with your own color. Zyan Drench has several modes: play against Android phone (with adjustable skill level), play solo (classic single-player mode), and network game. It is completely ad-free and open source.
KeePass is a light-weight and easy-to-use password manager that removes the need for you to remember many different passwords and makes it more feasible to use different passwords for each account. It manages your passwords in a secure database encrypted with AES and Twofish, which is locked with one master key or a key file.