Is it OK to copy terms of service/privacy policy from another site?

What is your alternative; get a lawyer to draw them up? Where do you think they get them from? Only 10% of legal documents are drawn up from scratch. Lawyers have a service called Westlaw. This service allows them to copy entire briefs/submissions made to the court by a lawyer in the past. They don't even need to come up with what to say in court, they just copy the person who was successful in the past. I spent 18 months in a NY law firm cutting and pasting.

IF IT AIN'T BROKE.....

My advice, take it from many websites, piece together the bits you want and use examples from other sites for different ways of saying the same thing. Change its wording slightly and put the sentences back to front sometimes. If it's altered, not in the same format and slightly different it's ok.

Just steal some free (= Creative Commons licensed) documents:

http://wordpress.com/tos/ http://automattic.com/privacy/

It depends on their terms of service.

Seriously, though, we wrote ours ourselves, but we did heavily use info we gleaned from other peoples' ToS. If you're just a generic web 2.0 site you can probably get away with using someone else's generic ToS, but if you're doing anything slightly different, you'll have to tailor it anyway.

FWIW, for microPledge we ended up with http://micropledge.com/conditions -- we got a lawyer friend to look over it briefly, and he gave us a few good pointers.

MySpace did it: http://news.ycombinator.com/item?id=3775