I haven't brewed anything very odd yet, but I once filled a growler with an ESB and 1/3 cup of maple syrup which very quickly showed an infection. I just left it alone for 3 months and then drank it. It was actually quite good.
chocolate jalepeno ale when i first started - had quite a kick- the last bottle 6 months after brewing was quite enjoyable though.
the mountain dew brew in my primary tasted pretty good from the hydro sample - time will tell.
beer, wine, cheese in various stages of production