One of the biggest downsides to the N800 as an Internet Tablet is that Nokia have sidestepped the issue of Calendars completely. However the N800 is the ideal device to carry around as a PDA replacement so why not capture some of those PDA features that make life easier to manage?
The first PDA tool that I needed on the N800 was a calendar. Searching the repositories I found GPE-Calendar, which is part of the GPE-PIM Suite. Its a tiny file so it isn't going to make a huge dent in your available storage and, although a bit basic, it does fulfill the functions that most people will require from a calendar (categories, multiple views, etc.)
And you can even publish your Outlook Calendar to it if you need to keep your work diary in sync.
Its a slightly convoluted process, so bear with me as I outline the steps:
First sign-up for a Gmail account, if you don't have one already, then go to http://www.syncmycal.com/ and download their outlook sync tool for Gmail.
Follow the instructions for syncing to Gmail's calendar and after a short setup you'll find you can fire a sync for a seven day period manually from an icon in the taskbar. If you pay for the full client you can set automatic synchronisation for any period you wish.
Once you've established a sync path between Outlook and Gmail you then need to setup GPE-Calendar to download the appointments onto your tablet. First go into Google Calendar and choose settings, then calendars and choose the calendar you wish to sybc with the N800. At the bottom of the page there is a private calendar section, click on the ical link and copy the URL you are given into a text document or email so that you can transfer it onto the tablet.
Open Calendar and then go to Tools, calendars and create a new calendar. Change the type to 'subscribe' and enter the URL copied above. Enter your gmail account details, set the sync frequency and you're done.
Now its not a complete solution, calendar traffic flows one way only, from Outlook into the Tablet. You can get around this by using Google Calendar as your primary tool for managing calendars, ensuring that both N800 and Outlook are always up to date.
There is another GPE-Calendar to Gmail Calendar sync tool which does offer two-way syncs and I'll be looking at that in the not-too distant future...