Grumpypants, technology edition

We use the Microsoft suite at work, and since we are a university and like to use the latest and greatest, we upgrade regularly.  Currently we are running Excel 2010, which uses the .xlsx file extension.

At home, the desktop is running a much older version - 2003, I believe, with the file extension .xls.

Never the twain shall meet. I have three four five choices if I need to take work home: 

1.  Save every dadgum file down in the .xls format on the thumb drive.
2.  Load a translator plug in on the home computer to allow the older software to read the new files.
3.  Upgrade the home computer to Windows 7 and purchase a copy of the Microsoft 2010 suite for home use (only ten bucks with our educators' discount)(but if I upgrade from Windows XP to 7, I will have to reload all my software - been there, done that once already this year - no thanks).
4.  Use my personal laptop to work at home, which already runs both Windows 7 and 2010 (but I cannot print from the laptop, and would have to repeat step #1 to transfer the files to the desktop to print).
5.  Whine, cry, and stay late at work to finish.

For some reason, none of these options are very appealing.  I most often use option #1, assuming I'm together enough at the end of the day to remember to save the files down a step.  It's a toss up at this point who I hate the most, Microsoft for the incompatible files, or my job.