I wrote a short article on FSQ a digital chat mode, works best with quick one line type chat messages. Its a channel based mode, so you often need to know where to look / listen.
Had a chat this afternoon with G4VLC Peter, G0VPJ John, G4DAX Dave on 5367.5 MHz USB. Links to the software and more info http://m0taz.co.uk/2015/12/fsq-on-5-mhz/
73 Dave M0TAZ