As a user (e.g. on a XenApp 6 published application or desktop, or Remote Desktop Session Host session) if you open Windows Explorer and click on My Computer you get some not so useful (to non-administrators) links. One of these is Uninstall or change a program.
How to get rid of it:
User Configuration, Policies, Administrative Templates, Control Panel, Programs: Hide the Programs Control Panel.
Clearly this will also remove the programs control panel, but you probably wanted that anyway…
This is possibly less obvious than you might think as you can also hide bits of the control panel by using the “Show only specified Control Panel items” policy setting, in which case you might not have disabled all the stuff that is not on your “show only” list.