geh is a simple command line image viewer with various nice features. It currently supports a slide-show mode displaying multiple images in a row either controlled by a time interval and/or mouse button clicks, and a thumbnail mode creating small thumbnail images and caching them in ~/.thumbnails according to freedesktop.org's thumbnail specification.
UnDBX is a tool to extract, recover, and undelete email messages from Outlook Express .dbx files. On first run, all messages are extracted as individual .eml files. Subsequent runs only update the output directory with new messages, and delete old .eml files that correspond to deleted messages in the .dbx file. Corrupted .dbx files (including files larger than 2GB) can be opened in recovery mode, in order to recover messages and partially undelete deleted messages. The success of recovery depends on the type and level of .dbx file corruption.
Redshiftgui changes the color temperature of your monitor to better match that of your surrounding. This means that it sets a cooler color temperature during the daytime (due to natural lighting) and sets a warmer temperature at night (due to indoor lighting). Similar to f.lux, this is a GUI port of the redshift project.
tmux-applets is a collection of tmux "applets" that are designed to be used in tmux's status bar. They are non-textual, using blocks of color instead. Currently, there are two applets provided. tmux-cpu-freq displays the CPU frequency level as colored blocks, and tmux-ping, which tries to ping a host and displays success or failure as a colored block.
YAGAC is a library that when linked to your C program, allows you to conveniently track or trash memory leaks within your application while it is still running. You can have multiple garbage collectors according the code part you are in. It tracks memory assigned by your code only, and does not monitor third part libraries. Tracking can be activated by updating a debug flag without restarting your application. It is intended for use with daemon-type programs.
utfout is a command-line tool that can produce UTF-8 (Unicode) strings in various ways and direct them to standard output, standard error, or direct to the terminal without the need for shell support. Strings can be repeated, delayed, randomly-generated, written to arbitrary file descriptors, interspersed with other characters, and generated using ranges. printf(1)-style escape sequences are supported along with extended escape sequences. utfout(1) sits somewhere between echo(1) and printf(1).