Vicious White Kids - Electric Ballroom, London - August 22, 1978. Sex Pistols, Longhorn Ballroom, Dallas, Texas - January 10, 1978. (This is the concert where Sid's bass comes unplugged and Steve Jones stops playing, walks over and plugs it in again - it is at about 6:30.) Bonus - Sex Pistols, Winterland, January 1978 - their final concert. (This has been an FPP previously but the link no longer works.) All links are Youtube. [more inside]
The first Sex Pistols show in the USA. (audio only) Atlanta, GA, January 5, 1978.
The Ramones Live: 26 Songs In 54 Minutes. Recorded at the Palladium, NYC, January 7, 1978.
YouTube.com: A New Musical Anthropology. A short essay on YouTube, and a long list of punk and hardcore concert videos. NSFW warning: If you go poking around the forum you'll find a lot of porno spam. I haven't checked out all the videos yet, so you're on your own there.