either export the calendar to a pst and import it at home or drag calendar
items to the usb stick and into the one at home. If you use 2007, you can
save as an ical (r-click on the calendar folder to see the options)

Create a new PST on the memory stick (File>New>Outlook Data FIle) and drag
your calendar folder to that PST.  Close the PST (right-click>Close) and
close Outlook.  Dismount the memory stick

On the other PC, after mouting the memory stick, open the PST on it in
Outlook with FIle>Open>Outlook Data File.  Open the calendar it contains,
switch to a table view like By Category, select all the items with CTRL-A,
then right-click and drag the selection to your default calendar or click
Edit>Copy to Folder, specifying your default calendar as the destination.