In this case the question is why would anyone (read PC user) To do this (maybe not needed and is committed to a clean look), But how to do so. Well, all in registry find solution, They are mains de tweakuri (Many still undiscovered by us).
So if you want to disable System Tray in Windows 7 (Applies to users Vista), Open registry Editor without fear and attack. :) Type regedit.exe in Searchacquis in Start Menu and follow the path HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionPoliciesExplorer. In the right pane create entry DWORD (32-bit) NoTrayItemsDisplay and give them value 1 (1 = enable; 0 = disable).
Then give Logoff / Logon for the change to take effect.
If you do then pity time left alone and left in the corner of the monitor and change your mind about it System Tray, then you just have to follow the same steps until NoTrayItemsDisplay and delete the entry or ii modify the value in 0. The clock will please: P.
Note: even if you send System Tray on the go, the applications that usually run in it will not be disabled, but only hidden. To disable it, uncheck it from Startup (Run-> msconfig-> startup).