This morning LHC machinists, experimentalists from the LHC experiments, as well as other CERN personnel gathered in the Main Auditorium at CERN to give their end-of-year report. After a LHC status report the spokespersons of ALICE, ATLAS, CMS, LHCB, and TOTEM briefly flashed their first experimental results, obtained from 900 GeV and 2.36 TeV collisions acquired in the course of the last three weeks.

The signature of large missing energy and jets is arguably one of the most important avenues for the study of potential new physics signatures at today's hadron colliders.

The above concept marks an interesting turn of events: the years of the glorification of charged leptons as the single most important tools for the discovery of rare production processes appears behind us. The W and Z discovery in 1983 by UA1 at CERN, or the top quark discovery by CDF and DZERO in 1995 at Fermilab, would have been impossible without the precise and clean detection of electrons and muons. However, with time we have understood that missing energy may be a more powerful tool for new discoveries.

Tomorrow I will be packing up and leaving CERN to fly back home, after a quite eventful, productive, extenuating, exhilarating week. The reason for my coming to Geneva was the CMS week, an event that takes place four times a year, and where a good fraction of the members of our 2400-strong collaboration gather to listen to updates of the experiment, the detector, the analyses, and to discuss rules, appointments, organizational issues.