What does the number sign thing (#) on facebook statuses mean?

[Taylor]

I see it all the time and i still dont know what it means..
like for example somebodys status is
"ready for tonight, who's all coming to the game? #missingyou"

is it like a sidenote or something?

[A.J.]

Usually it means someone is posting to Twitter and Facebook at the same time. People use the "#" (called a hashtag) to identify a topic they are discussing (i.e. #charliesheen). This way, people can search Twitter to see what the most popular topics are at any given time and comment on them.