A programmer should work as a limited user with admin access. That is, the programmer should be the admin of the machine, but while working, he should always use a limited user account.
If you need elevated rights to work, for anything but installing software, you're doing something very wrong. Worse, if you work as a power user or disable UAC prompts or the like, you're ignoring issues that will affect end-users of your software, forcing them to run with the same privileges you did. This is wrong.
This is true, irrespective of the operating system you're on. Though Windows seems to be the only one where where it comes up.
To clarify:
When I say the developer should be a limited user, I mean that they should have full admin rights to the machine, but when they test their code, it should be done in a limited-user environment. For example, the developer could be operating the machine as an Admin-capable user, but runs all tests in a virtual machine or in a limited user account. On Linux, this means simply that the dev has sudo
access; on Windows, this may mean an Administrator-level account with UAC and other security features fully enabled.