Want to generate your own QR code to use as your Avatar? Try out the tool I have uploaded at http://pratik.info/qrcode/
You can get the same php qrcode generator at http://phpqrcode.sourceforge.net/ or you can always use my site to generate the code for yourself 🙂
To add a custom message for users logging in via SSH you just need to make one small modification to the /etc/motd file
and enter the message you want to, something like
With great power comes great responsibility. Fire commands wisely!
Voila. This is done. Any one logging in via ssh will get the message you have entered