We present results of a signature-based search for new physics using a dijet plus missing transverse energy (E(T)) data sample collected in 2 fb⁻¹ of pp collisions at √s=1.96 TeV with the CDF II detector at the Fermilab Tevatron. We observe no significant event excess with respect to the standard model prediction and extract a 95% C.L. upper limit on the cross section times acceptance for a potential contribution from a nonstandard model process. The search is made by using novel, data-driven techniques for estimating backgrounds that are applicable to first searches at the LHC.