Capital Centre had the first video scoreboard

Here's a great "first" in game entertainment history, via Wikipedia:

"The Capital Centre (Washington, D.C.) was the first indoor arena to have a video replay screen on its center-hung scoreboard. The video screen was known as the "Telscreen" and predated the DiamondVision video screen at Dodger Stadium by seven years. It was also the first arena to be built with luxury boxes and a computerized turnstile system."