I've heard Postal 1 compared to Nine Inch Nails' The Downward Spiral. There definitely seems to be some noteworthy similarities between the two pieces, but what do you think some influences of the downward spiral may have been on Postal 1? No doubt, TDS was a land mark occasion in pop culture and influenced swathes of entertainment across all mediums.
Even then, much of the story in Postal 1 is paralleled rather clearly, especially in the concluding acts of both works.
https://www.youtube.com/watch?v=9URZGTHR3tAthe album for those who have managed to avoid it for 20 years. Seriously how could you? It was the best album of 1994 and one of the best releases of the 90s if not of all time.