Newegg offers the Brother WiFi All-in-One Inkjet Printer, model no. MFC-J450DW, which also copies, faxes, and scans, for $69.99 plus $1.99 for shipping. That's the lowest total price we could find by $7. It features 802.11g wireless, up to 6000x1200 dpi printing, up to 33 ppm, and USB 2.0. Deal ends September 20.
Update: Specs updated.