i once got dosed at a party in s.f. and had a similar experience... riding home, i was convinced i was in an entirely foriegn city... anyway, it was raining hard, i was completely bewildered, lost in a space/time continuum and s**t, when finally i saw a sign reading "s. van ness" and it hit me... "van ness, san francisco, yes, that is where i live, which must mean... that's where i AM!"... finally got home, at sunrise on the verge of hypothermia, slept til three pm and still felt stoned... i guess the moral of this story is to watch yer back at those beatnik parties... then again, this kinda thing happens to me fairly often...