Syncing Outlook Calendar between PC & Laptop

[#1]

I'm looking for a cheap (read free) way of doing what the title says.
Currently I copy the pst file from one computer to the other. But that doesn't help if I have appointments, etc. on the destination computer that are not on the original as they then get lost.
I can manually add appointments on each but that is time consuming. Is there a way to combine the calenders from both machines, simply and easily?
Cheers.
As an extra, once the laptop is updated I then want to use the bluetooth on that to update the mobile phone. But that should be easy

[#2]

one way would be to use Google Calendar with Google Calendar Synch to synch between then all.
I use that to help as part of my PC <> Mac <> Phone synching for my calendar.

[#3]

Thanks for that adiewoo.
Having paid for Outlook it seems wasteful to ingore it for a free on-line utility. I actually like Outlook  
Never having tried Google Calendar before can that be synced first with Outlook? If so then that would be a solution rather than having to re-type all data from Outlook (again).
Edit: Just been to the Google Calendar site and it seems it can be synced with Outlook so will give this a try

[#4]

Sorry don't think I explained myself...
Outlook <> Google calendar <> mac / phone
So I use it as the broker between Outlook and all my other calendars.

[#5]

Adiewoo, before I download the sync prog and register for Google Calendar it does state that the sync only works for XP (not 64 bit) and Vista. http://www.google.com/support/calendar/bin/answer.py?answer=98565
Do you know if it will work with W7 (both 32 & 64 bit)?  The PC is 32 and the laptop is 64.
Cheers.

[#6]

Haven't a clue I'm afraid - I only use it on win xp and server 2003...

[#7]

Thanks anyway.