the first non-BMC, eye-opening, beer we drank?
Way back in 1986 or so we had a beer co-op in our dorm. We'd buy whatever swill was cheap and use that to play quarters. Genesee Cream Ale, Red White and Blue, Pabst Blue Ribbon, Matt's and Kappy's were all favorites. Budweiser was the expensive beer for special occasions only.
One day someone came in with a case of odd looking beer. "What is it?" we asked. "Some beer they're selling real cheap at Kappy's. It's some new beer they're trying to get in the market or something." It was Sam Adams. We all tried it and agreed we didn't like it much, but if it was cheap we were all for it.
Well, it didn't stay cheap, and we quickly abandoned it. After college my tastes slowly changed. I went from Bud to Molson to Heineken and Amstel Light.
When I moved to San Diego, Karl Strauss was the popular hangout after work. It got so popular we christened it "Building K," and industry spies were known to go there to listen in on what we were doing. I started with their light stuff and worked my way slowly into IPA's and ambers.
When I met my (future) wife in 1995, she was a student in Portland. I went up there to see her several times and we went to Full Sail, McMenamins and the Lucky Lab. That's where I really started discovering beer.
Back in San Diego the local brewing scene was exploding, with Port/Lost Abbey, Alesmith, Ballast Point and Stone starting and/or expanding. It was all very incestual - Port Brewing took over Stone's building when they moved out, then Lost Abbey was created and used the same space. You'd see Mike the brewer working at Boulevard one weekend and the next weekend he'd be at Lost Abbey.
That's the time I really started learning about beer, talking to people about styles and listening to brewers critique the beers I was making.
So I guess for me there was no one "aha!" moment, just a long progression of changing times and changing tastes for me.