(I mostly link to their GnomeFiles.org pages because it's easier for me to extract URLs from its database -- saves me time putting this article together).
SportsTracker - An application for recording sporting activities.
PolarViewer - Viewer application for exercise files recorded with Polar heartrate monitors.
Bless - Hex Editor written in Gtk#
Galaxium Messenger - Instant Messenger for GNOME using the MSN service.
MooTag - MP3 and Ogg Vorbis tag editor for GNOME Desktop
GIB - Tool for building GNOME compliant icon themes.
Bluefunk - Bluefunk is a music player for the Gnome desktop.
CDCollect - CDCollect is a CD catalog application for gnome. It's goal is to be able to catalog your entire CD collection allowing for searches of your CD files with a clean and simple interface.
Chicken Framework - Useful .Net components for your application.
CSBoard - CSBoard is a small GUI for gnuchess.
DiaCanvas# - DiaCanvas# is a Mono binding for the popular DiaCanvas2
FastOpen - gnome-panel run dialog replacement
fewnn - fewnn is a frontend for different game emulators (such as xmame and tuxnes).
GCursor# - A simple application to change the cursor in X (written in GTK#).
GFax - The GFAX project aims to provide a free front end to the various facsimile programs available.
Gimp# - Gimp# is a C# wrapper around the GIMP API.
gTVListings - TV listings management program
iBookshelf - iBookshelf is an application for cataloging your book collection and designing bookshelves based on this data.
Indexator.NET - File indexer written in C# (mono). Can be used as a CD Cataloguer and gives facilties to consult data via console, graphic application and web.
Jumpnbumpmenu - Frontend to Jump 'n Bump
Kurush - Kurush aims to be an easy to use personal finance tool for the GNOME Desktop.
MonkeyPop - Chicken Framework client.
Tomboy Reminder Plugin - This plugin allows tomboy to show reminder popups at specified date in a tomboy note.
MonoUML - MonoUML. CASE tool for mono.
MVideo - MVideo is an advanced manager for your film collection.
NPlot - NPlot is a free charting library for .NET and supports various kinds of graphic modes.
opengl-sharp - C# binding for OpenGL including Gtk# OpenGL widget.
Scratchpad - Spatial text editor for the GNOME desktop
SkyNET - A simple skychart program for mono
Sonance - GNOME audio player based on GStreamer and Mono.
TerrarSharp - A small gtk-sharp/mono program to keep you updated with the current terror alert level.
WebNotes - Gnome Personal Wiki frontend (didiwiki).
WoodPusher - WoodPusher is a chess application written in C# for the Mono framework.
glyrics is a lyrics displayer and finder.
GSDict is GTK#-based frontend for SDict dictionary.
FileSync - File and directory synchronizing software
Edit# - Editor developed with GTK#
Sussen is a tool for testing the security posture of computers and other network devices.
GPuzzle - Simple puzzle based on Sam Loyd 14-15 game
Gnome Personal Web Sharing - A neat little application that lets you share your files over the web quickly and with no hassle.
mcatalog - An application for catalogue things like films and books.
Spam Trainer - Train your spam filter (e.g. Spambayes/SpamAssassin) via drag-n-drop in GNOME.
Conway's Game of Life - Conway's cellular automaton Game of Life.
Muine Applet - a GNOME panel applet for controlling Muine.
Monotheka - A DivX/XviD/DVD movie database for film buffs & collectors.
And there are more, out there, waiting to be used:
portage-sharp - portage-sharp is a gtk frontend for the Gentoo portage system
XBGM# is a free Xbox Game Manager.
C# Studio is a simple IDE for a C#/Mono/GTK# developer
GtkSharpRSS - A RSS and RDF client
GraphMonkey - graphic calculator. It uses a simple interface to draw curves.
Simplicity - A light-weight C# editor for Mono using Gtk#
Tam (Track Attribute Manager) jukebox is a system that randomly picks songs to play
SharpMusic is a client for the Music Player Daemon that tries to join the power of MPD with the visual appel of the Muine Music Player.
Gnosmirc - GNOme SMart IRc Client
Burro is an open source project with the goal of developing a cross-platform frontend to the mldonkey core.
RAF converter is a C/Gtk# program that opens, optimizes (gamma,saturation,sharpness, whitebalance, noice etc) and converts RAF files (Raw image files from FujiFilm Finepix s5000/s7000 digicams).
MediaNET is a Gtk# based free software content manager which allows anybody to find easily the media he wants to see/hear
Flash Card Recover
gMeshwork - a Linux meshwork client
If you know of more active GTK# projects, leave a comment and a URL on our comment section.