Logitech MK270 Full Size Wireless Keyboard and Mouse Combo - Black $19.99

With Amazon Prime you can get the Logitech MK270 wireless keyboard and mouse combo for $19.99. These are quite good for standard office tasks.

Reliable Plug and Play: The USB receiver provides a reliable wireless connection up to 33 ft (1), so you can forget about drop-outs and delays and you can take it wherever you use your computer
Type in Comfort: The design of this keyboard creates a comfortable typing experience thanks to the low-profile, quiet keys and standard layout with full-size F-keys, number pad, and arrow keys
Durable and Resilient: This full-size wireless keyboard features a spill-resistant design (2), durable keys and sturdy tilt legs with adjustable height
Long Battery Life: MK270 combo features a 36-month keyboard and 12-month mouse battery life (3), along with on/off switches allowing you to go months without the hassle of changing batteries
Easy to Use: This wireless keyboard and mouse combo features 8 multimedia hotkeys for instant access to the Internet, email, play/pause, and volume so you can easily check out your favorite sites
Comfortable Mouse: This compact wireless mouse is designed to be equally comfortable for both left- and right-handed users, plus its smooth cursor control allows easy navigation on most surfaces
Plastic parts in MK270 include certified post-consumer recycled plastic: 49% for the mouse and 54% for the keyboard.
Upgrade to Logitech MK540 Combo: Experience increased comfort with the MK540 combo, featuring scooped keys, palm rest, full-size mouse with soft rubber grips, and customizable shortcuts

$20