For an October revolution, dress warm.
That's the word going out - politely - on the Web to rally street protests on Saturday around the globe from New Zealand to Alaska via London, Frankfurt, Washington and, of course, New York, where the past month's Occupy Wall Street movement has inspired a worldwide yell of anger at banks and financiers.
How many will show up, let alone stay to camp out to disrupt city centres for days, or months, to come, is anyone's guess.
The hundreds at Manhattan's Zuccotti Park were calling for back-up on Friday, fearing imminent eviction. Rome expects tens of thousands at a national protest of more traditional stamp. Few other police forces expect more than a few thousand to turn out on the day for what is billed as an exercise in social media-spread, Arab Spring-inspired, grassroots democracy with an emphasis on peaceful, homespun debate.
In crisis-ravaged Athens, where big protests have seen violence at times of late, a sense of fatigue and futility may limit numbers on Saturday.
In Madrid, where thousands of young "indignados", or "angry ones", camped out for weeks, many also feel the movement has run out of steam since the summer.
Asian authorities and businesses may have less to fear, since most of their economies are still growing strongly.