I just got a mailing on this:

Circus Circus
$34.95 per night, tower rooms (Sun-Thu)
Book online at http://circuscircus.com and enter promo code: WINTR1

$25 Free slot play
2 for 1 dinner buffet
20% off garden grill
$4 off Adventuredome
FREE funbook ($100 value)

Valid Nov. 18, - Jan. 31, 2008, Excludes weekends, holidays, conventions. Two night minimum stay. Subject to availability. Advance reservations required. Must be 21 or older.