The GUIShell project is a collection of utilities facilitating the use of the GTK+ toolkit in shell scripts through the gtkshell utility. The ACE configuration environment provides sample scripts utilizing gtkshell for desktop utilities. rootcat provides the ability to display messages to the root window using Xft, allowing one to write status display scripts.
Famflows is a program which tracks "flows" of energy and materials inside a household. It has an alternative approach from double entry accounting systems. In those systems (like gnucash or jgnash), the transactions are balanced in numeric value. In famflows, instead, the transactions are balanced in the conversion, but not in the numeric value.
Secluded Notes is a simple text editor that keeps each document as a part of its own executable. That part is called an "attachment", and the program encrypts/decrypts it on the fly with an AES 128-bit cipher. As long as you close the application, it automatically updates itself for the next run.