We don't wear bell-bottoms at our house, but we do love some things from that era, namely lava lamps.
We've been finding them at garage sales, estate sales, rummage sales — whatever kind of sale we run upon. We also have one lamp that is cylindrical with glitter but heats up awfully fast and another one shaped like these that has probably been made more recently and is kind of flickery like an lcd light or something.
Somehow they found their way onto the tall kitchen counter and they seem to get turned on at least once a day to do their thing. I never had a lava lamp when I was growing up, so it's been kind of fun to enjoy them with my kids.