The Brother HL-5370DW is a perfect fit. It's ~$200 depending on where you look online, and fits your criteria of wireless with duplexing. I bought this printer from a great Office Depot sale back in July, and it has worked great. Although I haven't used up my starter toner yet, replacement toner appears to be affordable (~$80 for a cartridge rated for 8,000 pages). Prints quickly even in duplex, and has a fairly small footprint. Wireless setup can be a bit of a pain depending on whether or not your router supports certain quick-setup technologies, but once everything is set up it works great.