I recently received an offer of the Marriott Signature card with 1st year fee
waived, 15000 points after first purchase and one free night at a Marriott
hotel. Offer came as e-mail for weekend specials and was to celebrate(?)
20th anniversary.

That is worth at least 2 days free hotel for no cash expenditure. not bad.
There is a similar thread on the Marriott board on this item, but deserves mention here.