Next year will be "A Very Special Metric Day" (10/10/10), so why not get in some practice today? Three doesn't have to be the only magic number out there; and, isn't base 10 much easier to deal with?
Celebrate all things metric today. The National Council of Math Teachers (NCTM) has a nice page on ways to get your 10 on (even if they forgot to update it for 2009) as does the US Metric Association. Check out the Metric Olympics Events. Go wild on this Saturday night!