The Linux version of QuicklyChat is highly experimental. Feel free to try it out, and let us know if you run into any issues. The instructions provided are for 64-bit Ubuntu 12.04 with default settings.
QuicklyChat runs on Adobe Air. Adobe no longer supports Air, but you can still get an old copy running on Ubuntu or Red Hat.
Or, in code-block form (again, assuming 64-bit Ubuntu 12.04):
sudo apt-get install ia32-libs-multiarch;
sudo ln -s /usr/lib/x86_64-linux-gnu/libgnome-keyring.so.0 /usr/lib/;
wget http://airdownload.adobe.com/air/lin/download/2.6/AdobeAIRInstaller.bin -O /tmp/airinstaller.bin;
chmod +x /tmp/airinstaller.bin;
/tmp/airinstaller.bin;
wget https://www.videable.com/beta/quicklychat-installer.air -O /tmp/quicklychat-installer.air;
Adobe\ AIR\ Application\ Installer /tmp/quicklychat-installer.air;
QuicklyChat should now be installed.
If you have any problems, please email linux-support@quicklychat.com.