Lakers.
I have no on-going feeling for any other team. Temporary dislike has ocurred from time to time for Knicks, Heat, Sixers, Pistons and a couple others. But that can change year to year. Only the Lakers are constant.
And for young folks that don't understand, remember the only statistic in sports that should matter to a Celtics fan: 17. And take note of the team that took 5 with them from Minneapolis and escaped from winter misery to glitz, glamour, Nicholson, year-round summer and bottomless pockets. Right now sitting in Beverly Hills homes with 16 banners and Cheshire Cat grins awaiting the FA class of 2014.