1. I desperately want to be able to send a link to somebody and have them be able to book a N-minute meeting on my calendar (CalDav) without any further interaction. I have spent probably several hours trying out products, all of which suck. I currently spend $30/month on a tool that really doesn't even work.
2. The enterprise IM (CampFire, HipChat, etc.) is pretty well done at this point, but the "group chat for the somewhat public" space isn't. If I am supporting an open-source project the only game in town is IRC, which is hard to use for people who need support. If I want to have a permanent chatroom with 15 software developers that I know socially and allow people to drop in, there's no system for that.