Newegg offers the Microsoft Desktop 800 Wireless Keyboard and Mouse, model no. 2LF-00001, for $19.99 with free shipping. (Amazon has it for the same price for Prime members.) That's tied with our July mention and the lowest total price we could find by $5. This set features a wireless range of up to 30 feet; the keyboard includes hot keys and the mouse has 1,000 dpi.
Select third party merchants via Amazon offer the FAVI Entertainment Wireless Keyboard, model no. FE01-BL, with prices starting from $15.99. Plus, Prime members receive free shipping. (Non-members can pad their orders over $35 to get free shipping; otherwise it adds $8.35.) That's a buck under our July mention and the lowest total price we've seen. (It's a current low by $7.) It features a 3-in-1 multimedia wireless keyboard, built-in rechargeable lithium-ion battery, and a 2.4GHz USB wireless receiver.