Software or web solution to a kind of shared diary

[peige]

We want to have a shared diary page, with customer contacts we have made that ideally self updates so we can keep track of what each other is doing and has said. Twitter set to private would have been ideal but it only gives you 140 characters per update which isn't enough.

Can be web based or something we just run on our network..

Any suggestions, needs to be fairly easy to use or it won't get used