This is my kind of topic as well! I am a quasi beer snob myself, I lived in Colorado for 7 years and I ate the most crappy inexpensive food just so I could afford good beer!
Top 5 is even really hard but I'll try in no particular order.......
-Tommy Knockers Maple Nut Brown
-Sierra Nevada Pale Ale
-Carlsbad Chronic(I swear it's a beer!)
Although the best beer that I've ever had in my life, because of situation, was a Guiness. And the ONLY reason...and I mean ONLY reason is because it was the first beer I had in over 7 months while flying back to the States after a tour in Ar Ramadi, Iraq. It was 0530 when we landed in Shannon Ireland and they had Guiness and Beamish Red lined up for us, and holy *&^$%#$ was it GOOD! I don't even like Guiness! It was a well deserved beer!