There are few words in the English language as thrilling to classic car collectors as “offered without reserve.”

They represent, however improbably, the opportunity to snag an enviable example at a “bargain” price.

Of course, that frequently leads to even fiercer bidding, but so be it; there’s fun in the frenzy, nonetheless.

Offered without reserve at RM Auctions’ upcoming Arizona sale in January

Guaranteed to inspire some action on that front is this gorgeous 1957 Mercedes-Benz 300SL Roadster from RM Auctions’ upcoming Arizona sale on January 19-20.

The topless version of the famed Gullwing, pristine 300SL Roadsters can command $500,000 or more.

Of course, you might get lucky…

Images Darin Schnabel ©2011 Courtesy of RM Auctions; click to enlarge: