Newegg again offers the refurbished Logitech MK520 Wireless Desktop Keyboard and Mouse Combo, model no. 920-002553, for $19.99. Apply coupon code "VISACHECKOUT" and check out via Visa Checkout to cut the price to $17.99. With free shipping, that ties last month's mention as the the lowest price we've seen. (It's also a current price low for a refurb by $7.) This mouse and keyboard set features ergonomic design and 2.4GHz wireless connectivity, with up to three years of battery life for the keyboard and up to one year for the mouse. Deal ends October 30.
A 90-day warranty applies, but it's unclear who backs it.