Sadly most of the good beers in my life have come from a bottle, but personally something about beer on tap is just magical to me and I really enjoy it a lot. I saw that in lucky BC Canada someone was getting a Cantillion tap takeover! I've never even had Cantillon from the bottle! So here goes: Duvel (IMO Duvel from the bottle doesnt compare and i dont really care if this has a lower abv, in fact all the better as i am not trying to get wasted). Blaches de Bruxes- White beer i think is meant to be consumed as fresh as possible. Bottle is pretty decent, but the tap was sublime and perfect for a summer day. Liefmans Gudenband- Delightfull. Black butte porter- When this stopped being a popular staple in most bars years ago I was beside myself. the bottle is NOT the same.
Two stand out for me that were stupendously deliciious at the time for numerous reasons in addition to just being great beers: Hercules Double IPA Delirium Tremens
Off the top of my head.... Pliny Blind Pig Zombie Dust Black Note Stout Hercules Oscar Blues lineup 90 Minute Hopslam
The Apex DIPA from Bear Republic stands out in my mind. It's always great to go to a bar and try something you've never had or even heard of. That stuff was delicious. Also... Santa's Little Helper RIS Hibernation Old Ale
I also drink most of my beers from out of a bottle. I have had mixed experiences with Two Hearted. The first time I had it on tap it blew me away, the second time I had it on tap it was just alright. Hopslam blows me away every time I have it on tap!
IPA's on tap (as long as they're fresh - which they generally tend to be) are pretty awesome compared to their bottled counterparts. PtE fresh from the keg is nothing less than miraculous.
La Trappe Quad is awesomer on draught. The most recent memorable one was probably Rushing Duck War Elephant- hopefully it becomes a yearly thing for them: http://beeradvocate.com/beer/profile/29800/85357
The single best beer I ever had was a Founder's Double Trouble on guest tap at Three Floyds a few years back.
Pliny The Younger, Grand Teton Double Vision Doppelbock, Snake River Pandemonium Quad, Sierra Nevada Celebration, Snake River Pako's IPA, Odell Myrcenary DIPA, and more..
Firestone Walker Union Jack on tap at my cousin's kid's Bat Mitzvah. Bottles are great; tap even better.
Old Rasputin, Bling Pig, Matilda. If Old Rasputin is served properly, then you have a nice delicious hoppy milkshake on yer hands.
I had FW Parabola on tap today. Their theme for next month is barleywine, so I'm hoping they'll have FW §ucaba (Abacus) on tap next week.
Some memorable ones for me: PtE KBS curmudgeon's better half 2 Yr old BA aged Double Bastard(Best bear I've ever had) FSW XVI Black Butte XIIV Mix Tape Vol 2 (Very interesting wouldn't want again)
At Brouwer's Back In Black Stout Fest last year I was fortunate enough to try Fremont's Kentucky Dark Star. Mind is still blown.
I foolishly believed Bell's Two Hearted to be over rated a tad until I had it on tap last Saturday. I have a new appreciation for this beer and it is a new favorite.
Pliny was really really good, but not too different from the bottle. Two that I would like to mention are high ABV brews that were just completely different on tap than out of the bottle. Avery's The Beast and Rogue's Old Crustacean. I don't know where the difference comes from with it being on tap, but damn! The Beast was much smoother and seemed sweeter than from the bottle, meanwhile Old Crustacean on tap was almost like drinking straight whiskey. It was potent to say the least.
1.Hopslam 2.Third Coast Old Ale 3.Backwoods Bastard 4.Narwhal 5.GI Fleur(i have a secret passion for this beer)