The Collaborative International Dictionary of English v.0.48:

Valueless \Val"ue*less\, a.
   Being of no value; having no worth.
   [1913 Webster]

WordNet (r) 3.0 (2006):

valueless
    adj 1: of no value

Moby Thesaurus II by Grady Ward, 1.0:

50 Moby Thesaurus words for "valueless":
   NG, beggarly, beneath contempt, cheap, cheesy, common,
   contemptible, crummy, despicable, gaudy, gimcracky,
   good-for-naught, good-for-nothing, junk, junky, mean, meretricious,
   miserable, no-account, no-good, not worth having,
   not worth mentioning, not worthwhile, nugacious, nugatory, paltry,
   pathetic, pitiable, pitiful, poor, rubbishy, sad, scrubby, scruffy,
   scummy, scurvy, scuzzy, shabby, shoddy, sorry, trashy, trivial,
   trumpery, two-for-a-cent, two-for-a-penny, twopenny,
   twopenny-halfpenny, vile, worthless, wretched