I have some different ones from the rest of you, haven't seen much love for British Alternative in the thread! hehe And then I have some similar ones to the rest. No particular order, though it seems to be chronological:
Alice in Chains with The Deftones and Mastodon 2010 at Red Rocks Amphitheater
James Taylor - 2008 Greek Theater Berkeley
Metallica with Korn New Years Eve 1996 HP Pavilion San Jose
Oingo Boingo - 1995 Close to Halloween on their farewell tour (so one of their last shows ever...might have been second to last if I remember correctly) at Great America Amphitheater
Pink Floyd - Momentary Lapse of Reason tour early to mid 90s at the Oakland Colosseum
Depeche Mode with Nitzer Ebb and Electronic - 1990 World Domination tour at Dodger Stadium
New Order with The Sugar Cubes, Public Image Limited - 1989 at The Irvine Meadows Amphitheater
Huey Lewis and the News - 1985 Mid State Fair in Paso Robles. Power of Love and Back to the Future just came out and I was a fan, so it was a fun show. I was also 14.
The Glenn Miller Orchestra (and yes I know, not the original since Glenn died in a plane crash in 1944! hehe) - probably 1981-1983 time frame at the San Diego Zoo or it might have been LA Zoo...I can't remember. What I do know is that as a 12 or 13 year old I was not looking forward to it, especially since I was on a senior citizen trip with my grandma but I found that I really dug the music, and the full orchestra...and it woke in me a lifelong love of big band music, and jazz, and most music actually since it got me out of my bubble to look at other genres. And I've been able to pass that along to my kids as well.
Eddie Rabbit - 1979-1980 time frame at the Mid State Fair in Paso Robles...not necessarily a fan, though at the time I loved me a rainy night, but he gets special mention because it was my very first concert.
I saw a couple of those big all day festival type concerts (like Loolapalooza) in the 90s too, though both were tied to the SF Bay Area, one for for KOME, a now-defunct radio station and one for the Bridge School, both were held at Shoreline Meadows Amphitheater in Mountain View:
Bridge School Concert XI 1997 (and all acoustic) - Neil Young (solo), Metallica, Lou Reed, Smashing Pumpkins with Marilyn Manson, Alanis Morrisette, Dave Mathews Band, Blues Traveler, Kacey Crowley, and Crosby Stills & Nash.
Camp KOME 1997 - Social Distortion, Sugar Ray, Ben Harper, Violent Femmes, Local H, Matchbox 20, Dance Hall Crashers, Cake, Fiona Apple, Third Eye Blind, Smash Mouth, The Marginal Prophets, Stem, MXPX, Less Than Jake, Salmon, Buck O' Nine, Blink 182, and Reel Big Fish.