Gnome Color Chooser is a GTK+/GNOME desktop appearance customization tool. It can change the colors for almost anything on your desktop, including the panel colors (font, etc). Unlike applications like Murrine Configurator, this utility does not modify your original themes. This way you can keep sharing your themes without any license or naming conflicts.
Nautilus (the GNOME file manager) is able to display thumbnails for several file types: images, video, audio (holding you mouse over a sound file for a few second), text, pdf, etc.
Here are 5 of the most popular, standalone feed reader applications for Linux. I didn't include feed readers which come with applications like Firefox, Opera or Thunderbird for example, but these can also be considered a viable alternative to the ones below.
For new we can only speculate on how good Chrome OS will be or how it will look. But if you want something that might look like Chrome OS and still use your favourite Linux distribution, try Chrome-Like Theme Pack.
Gnac is an easy to use audio conversion program for the Gnome desktop. It is designed to be powerful but simple! It provides easy audio files conversion between all GStreamer supported audio formats.
The new GNOME release will do away with icons on menu items and on dialog buttons. The exceptions are menu items which represent a dynamic object such as applications, files or bookmarks, and devices. This obviously means that the GNOME panel, as well as the panel menus, will still show icons for their items.
Cairo Menu is a fast and functional menu for the Gnome desktop that focuses on speed, efficiency and delivering what you want in the least number of clicks or keystrokes. Even though it somewhat resembles Gnomenu, the author claims Cairo Menu is much faster and brings a number of new concepts and features for this new menu.
To integrate Google Calendar events into your Gnome desktop, go to Google Calendar, click on "Settings", then on the "Calendars" tab and then on your calendar's name:
Linux starts many processes with priority 0, which is the highest priority (as the rule of thumb is that the lower the number, the greater the priority). If you are running any resource hungry application then this priority mechanism causes some problems.
Gnome system restrictions utility Lockdown Editor lets you create a profile that limits a user to a set of application that a system administrator allows. It has a nice, logically structured GUI that allows administrators to choose and click checkboxes on the options that you want to deny for user access.
One Hundred Paper Cuts is a project which attempts to fix 100 usability errors reported by the users for the new Ubuntu 9.10 Karmic Koala.
GShutdown is an advanced shutdown utility which allows you to schedule the shutdown or the restart of your computer, or logout your actual session.
Quod Libet is a GTK music player written in Python with support for various audio formats, including Ogg Vorbis, FLAC, MP3, WAV, MP4 and WMA. Quod Libet has a different interface and a slightly different approach compared to players like Rhythmbox or Banshee, for example.
Gnome-Art Next Generation is the successor of Gnome-Art and lets you change your Gnome-themes (icon-, wallpaper-, splash-,...-themes) with one click. It is in an early stage and under development but it looks very promising already.
Rhythmbox is the default audio player coming with the GNOME desktop environment, featuring a clean, typical interface which is so common for GTK audio players. I could say that Rhythmbox has little missing features and it is rather complete.
The GNOME-Colors is a project that aims to make the GNOME desktop as elegant, consistent and colorful as possible.