A feeling common during the month of December. It is the need to buy many overpriced gifts for your family, normally on a credit card. The buyer feels no feelings of regret for the rest of the month, as he/she feels they are being a good person. The Christmas buzz is always followed by the New Year's hangover, when the credit card bill comes in and the buyer goes on a rant about how much money they have spent.
You're buying a nintendo wii off ebay for 500 dollars for your kid? Must be the Christmas buzz.