First beer to blow your mind.

I'm gonna get slammed for this, but SA Boston Lager. I actually tasted and enjoyed Octoberfest prior (which is what opened my eyes to better beer), but Boston Lager blew me away, and still remains one of my desert island beers.
Others (also on that desert island list) - Duvel, Orval, Two-Hearted...

 

Alpine Duet. Still blows my mind.

 

90 Minute on tap blew me away the first time.

 

First OMG, this is excellent was Ruination. First OMG this is orgasmic was PtE.

 

Alpine duet

 

Backwoods Bastard.

Had it on draft in a bar in NYC. It was delivered and I could smell it as the bartender got closer to me. I sat there sipping and sniffing that thing for about an hour, thinking to myself, "wow...wow...wow...wow." I may not have been good company for that hour.

 

Gaffel Koelsch, my first beer, blew my mind. But the beer that turned me on to American craft beers once I got back home was SA Boston Lager. It's still a great beer and I never hesitate to grab it when it's fresh.

 

Weihenstephaner Hefeweissbier on tap at The Farmhouse in Burlington VT. Not as good in the bottles I've had since, but still a bloody amazing beer.

On the opposite end, I literally said "Ugh" as I cringed at my first sip of Stone's Ruination, only to realize that I was going for a second sip even as I was wondering if I could finish it. Horribly wonderful.

 

As a BMC drinker, Highland Black Mocha Stout

 

Bridgeport IPA was one of the first beers I had when I moved to Portland. Incredibly juicy stuff. I still love it.

 

Schlenkerla Maerzen. Hated it the first time. When it first blew my mind: after I finally made it through beers #1 & 2 and got to #3...the way the smoke took a back seat to the underlying caramel-y Maerzen. Made it all the way to about #6 or 7 that night. To this day, every time I order #3, I prepare to have my mind blown. I still don't understand how that beer can be so good.

 

Same...I thought I'd puke the first time, but after a few I found it enjoyable.

 

KBS - I didn't realize the range of flavors that could be brewed into a beer before I tasted KBS.

 

I distinctly remember saying "wow" upon smelling and tasting Alpine Duet for the first time.

 

Mine is either Anchor Steam, it got me into craft beer. Which is why I have the anchor tattooed on my wrist. Or Anchorage Galaxy White IPA. It wasn't to hoppy, had a nice wheat balance, and a little sour end. Very surprised by this one.

 

When I was just first starting, probably Double Bastard and Speedway Stout. Once I was a little more entrenched, Parabola.

 

Definitely Rochefort 10

 

Stone IRS. First IRS I ever had.

 

Chimay Red

 

Not long after I started trying new beers, I picked up a Peche Mortel on a whim. I then realized I loved imperials stouts, and that despite what I had thought the past 25 years of my life, I DO like coffee...a lot! In my beer at least ;-)