best drug trip depicted in a film?

it seems like this question hasn't been asked in a while. and i have seen many bad attempts. that being said, no two people or drug trips are the same. so it's already a difficult task. i think the best i've seen was actually in an old volkswagen cabrio commercial with some kids driving at night to 'pink moon' by nick drake. (what? they're all grinding their teeth, clearly on ecstacy!) anyway, what do you think? has anyone nailed it or even come close?