You will be paying it either from your back skin or paying someone else to do it. How much does you work cost? I would pick Office 365 but thats just me. Some points from O365: Outlook for Windows and Mac, ActiveSync native support on every decent mobile hardware (mail, calendar, contacts sync), Outlook Web Access (webmail), IMAP/POP/SMTP support, shared resource calendars and shared contacts possible trough Sharepoint. Some more advanced things may require some powershell magic.

It costs and requires Windows + IIS + MSSQL server (Express) but I haven't found any really equivalent at open source side. http://www.thycotic.com/ But then you need only browser to access it. Its perfect for scenario where you have team of admins etc who need to share tons of password with each other.

So you buy today cool car which has iPad integrated all over, how you will feel it after 10 years? Or do we in future scrap car after 2-3 years of use? That said got quite new Jetta with simplest possible radio module with black&white UI interface and its doing it job properly. It even got 3.5mm AUX in, where I can plug in anything from C cassette Walkman to Android Phone with Spotify. Sure its not so stylish&trendy but its easier change phones and software than whole car. I might be old fashioned but I use car primaly for driving.