Just a few:
Brother HL-5240 $200
HP Laserjet 1020 $180
Samsung ML-2250 $180
These are list prices, and if you search the web for a deal, I.E., instant rebates, refurbished items, etc. you may find one of these for much less.
HP has a refurbished LJ1020 on their web site for $125. Hope this helps.
Greg
Hello,
I'd like to know, what's the cheapest laser printer capable of printing 1200x1200 dpi in monochrome?
Thanks.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic