Making $2-300/month off Android apps (AdMob). Despite best efforts, this is dominated by a soundboard app. Not what I expected, but we'll take it!

Internet yellow pages, www.ablocal.com, doing quite well. Can't disclose metrics, but it makes more than you probably would guess.

Domain sales - again can't disclose specifics, but in the $xx,xxx range this year from domains. Not a huge portfolio, but some good ones.

And we just launched Gold Plugins (last Friday), a membership club for our premium WordPress plugins. Hoping it will become a good vehicle, although we do pride ourselves on awesome support, so not that passive. Previously, we were selling these plugins separately, for about $1k/month. No stats on the membership system yet.

Gold Plugins: http://goldplugins.com/

I have some others, but nothing that's making enough money to be interesting! I'll add more if I think of them; we have a bunch of random properties.