Citrix Receiver creates a system tray icon, you might not like that in some situations.
To hide or remove the icon we can create a registry entry for every single user.
HKEY_CURRENT_USERSoftwareCitrixReceiverShowIcon (REG_DWORD) with the value 0.
We can set this in a SCCM or MDT task sequence if we use to Default User settings as explained here: http://larslohmann.blogspot.dk/2013/03/customize-settings-for-all-new-users-on.html
Reg.exe Add “HKUDefUserSoftwareCitrixReceiver” /v ShowIcon /t REG_DWORD /d 0 /f
And the icon is gone: