From my profile:
"Senior EMC Technologist at a facility that assesses the emissions and immunity of electronic equipment, to see if it meets the requirements imposed by government bodies like the FCC, Industry Canada, ETSI, IEC, AusTel (now ACC), VICC, etc."
Basically, we listen to new products in a quiet environment to see if they make too much noise.
Then we put the sample in various hostile environments to see if they will continue to function normally under conditions that are likely to be encountered in the real world.
Yeah, I get to play with cool new stuff before it hits the market! :D