i have fully migrated to gmail last year. it has everything outlook has and performs much better. it allows to store as much info as you wish and it is extremely reliable, customizable and feature rich. but wait, google calendar which comes along with gmail, is even better. it allows to share and browse for public calendars, manage multiple agendas, sync up with every piece of portable hardware you might imagine of and has exceptional usability. both come with a superb notifier that alerts you of any important event/message.
all of this is accomplished with almost no cpu power consumption and you have your data permanently secured on google servers.