For music lovers who don't know about the web site Concert Vault, I recommend checking it out. They have digital recordings of over 1,300 concerts, most of them available for free. Shows come from several sources, including archives from Bill Graham's venues and the old King Biscuit Flower Hour.
You can listen to an entire concert, maybe the Jimi Hendrix Experience at Winterland in 1968, or put together individual tracks in a playlist. Or you can try out random programming from each of the four main catalogs.
The range of music is pretty good. Obviously, with the Graham archives, you get a lot of 60s and 70s shows by the biggies: Hendrix, Stones, The Who, Pink Floyd, Zeppelin, Clapton, The Dead, Jefferson Airplane and Creedence Clearwater Revival, as well as gigs by San Francisco groups like Electric Flag, It's a Beautiful Day, and Quicksilver Messenger Service. The King Biscuit catalog includes concerts from the 1970s and 1980s by artists like The Kinks, The Clash, Talking Heads, U2, Blondie, the Cure, etc. There's even a country archive, which includes folks like Waylon Jennings, Jerry Jeff Walker and Kris Kristofferson. (Alas, no Willie Nelson, who was doing some wonderful shows in the 1970s.)
There's David Bowie at Nassau Coliseum in 1976 and the Clash at the Agora Ballroom in 1979. Bruce Springsteen plays Max's Kansas City in 1973, just a few weeks after his first LP, Greetings from Asbury Park, was released. Or catch him in the longest show I've seen in the vault so far, a 1978 gig at Winterland. Both Lou Reed and Jerry Jeff Walker show up at the Bottom Line in the late 1970s; Bruce Cockburn - having just returned from Nicaragua - plays a short, intense set from 1984; and there's part of John Lennon's show at a 1972 benefit concert at Madison Square Garden. You can even hear a short set by Talking Heads at CBGB's in 1977.
And there are more recent shows, including the I'm Not There concert last November at Beacon Theatre, with many of the groups who performed on the soundtrack of Todd Hayne's film about Bob Dylan. Guests include Lee Renaldo, from Sonic Youth, and Yo La Tengo, as well as a brief appearance by Heath Ledger.
At the moment, I'm listening to Neil Young & Crazy Horse at Fillmore East (NY) on March 6, 1970 - the early show.
Here's a rocking 14-minute version of "Cowgirl in the Sand" that closed out the program: