We played a good one at my departmental christmas dinner last year.
Got plenty of plasticine or various colours, a timer and several piece of card.
On the card write various objects (can be seasonally related ie if played at Xms, or can be stuff related to your workplace etc etc) should be things people would be able to guess.
Take it in turns to draw a card and within a time limit (a minute is good) that person has to try to make the item out of the plasticine, if they do a good job and people can guess their item, they win the card.
Play several rounds and whoever has the most cards at the end can win a prize or whatever.
