(a) Having a spicy meal
Usually whatever it is that the Indian restaurant serves. Cobra beer I think.
(b) When you are outside and it is over 85 degrees Farenheit
Something pretty weak but fairly tasty. There's a Madeiran beer (Coral or something, I forget) which is just the thing for when you're out somewhere hot, and want to wind down without the alcohol knocking you down.
(c) You have just left work and you go to your favorite bar and want to unwind
I quite like Leffe. It's widely available and tastes of more than cat piss.
(d) You are eating pizza
Whatever's to hand really... it's not going to make a lot of difference.
(e) You are out on a date
No beer unless she orders one (to date: never). I prefer wine for 'involved drinking' in any case.
(f) You just want to savor the flavor
I'll work down the menu at
Belgo. You might say it's not authentically Belgian, but I'm not all that keen on going to Belgium even for business.
Re: the Guiness thing, you'd be amazed at the R&D (& the costs) that went into developing that widget + canning method which 'gasses' and 'stirs' the beer for the draught taste. I was stunned at the effort that went into it.