Evernote is an amazing app that lives on a server, your laptop, smart phone, wherever, and syncs notes, images, photos, between them all. Data can be shared. I use it to keep notes on the status of client projects as well as for notes about WordPress, images of important documents, and remembering where I parked the car at at airport (by taking an iPhone photo of the location marker the car is near then sending it to Evernote with notes.)
Patrick Albrecht in Atlanta runs three restaurants by using Evernote and sharing documents and notes with employees, contractors, and vendors. Sure, this is from the Evernote blog, but it shows how smart phones and the cloud have real life business applications.
Evernote has free and paid accounts. You can store virtually anything on it, arranged into folders and with tags.