My friend Karen asked me about free wiki software. Here is my response
Well, PBWiki (http://pbworks.com/) offers advertiser supported wiki services but I really really really (really!) recommend using Mediawiki instead. Mediawiki is the software that runs the FLG wiki. It’s really good software and it’s what users are familiar with. I run it on Dreamhost.com. If your friend has an ounce of geek in them, they should sign up and run their own wiki. And if they don’t have an ounce, they probably shouldn’t be running a wiki, really.
Dreamhost service is like $8/month. I have a coupon-thing where they’ll get $48.50 off a $96 1 year membership or $25 off a monthly. My promocode: SPLITITWITHLEE
Oh and I see that they have a free trial thing on their homepage: http://dreamhost.com/
If your friend can find a friend that already has a hosting plan at Dreamhost or another provider, they might let them mooch off them for free since it probably won’t cost any money extra. That’s what I do for SWARM and FLG and some personal wikis I run.