Allin1 is a little dock applet for FluxBox and similar window managers. It monitors CPU load with a moving graph, memory and swap usage with histograms, battery and power status with histogram and icons, ethernet/PPP interfaces with icons and histograms (linear or logaritmic), filesystem space, and Seti@home progress.
The goal of the General Applet Interface Library is to give programmers a simple yet powerful applet interface. This library supports wmapplet/dockapps, GNOME 2 panel applets, and ROX panel applets. The applet programmer doesn't have to care about where the applet will be used, since the library handles that. Over 50% of the code in a dockapp and a GNOME 2 Panel applet does only one thing, setting up the applet window. With GAI, this can be reduced to just a few lines of code.
Pop3eye is a POP3 email notifier. It can be placed in a "dock", or use a regular or undecorated popup window. Regular expressions are used to filter email. It can display up to 20 partial lines of the email body in a tooltip window. It can monitor and display an unlimited number of accounts. You can choose to show messages using regular expressions, or delete messages from the server.