Not at work, but a gym that I used to belong to did this for several years.
The "winners" always gained back all of the weight before the next year's contest. They decided that encouraging fast weight-loss was unethical and stopped doing the contest.
Dances: salsa (standard/LA), casino, rueda de casino, cumbia Colombiana, bachata, mambo, cha-cha-chá, merengue, reggaetón.
Currently learning: Mexican cumbia, danzón, Cuban rumba
Dances to Learn in the future: flamenco, tango Argentino, samba, belly dancing, bhangra, ballroom rumba
| current weight: 212.0