Batninth:
Try using the app named Evolution. Not only is it an email client (and has connectivity to Exchange servers) but it also has Task lists, Contacts, Calendars and Memos. I very nice productivity application. Does everything MS Outlook does, and then some.
For another very fine personal productivity app try OpenOffice: Spreadsheets, Word Processing, Presentation, Database, and Drawing applications all in one. You can open MS Word documents, for example, and save OpenOffice documents in MS Word format.