For the last few years while some are going with wireless/cordless models the
Microsoft line along with Logitech has been looked over. The MS keyboards as a rule have an adapter to run on usb as well as standard plugin. Adapter on standard plugin - adapter off usb port. Currently running the MS Media Pro.
That one has a magnifying tab on the left side for zooming in on text. You can
see the Microsoft line is favored here while keeping an eye on Logitech too.