It's May 4, which means Star Wars fans, Twitter users and everyone in between will be greeting each other with May the fourth be with you messages all day long.

The pun-filled fan-created holiday, recognized by many as Star Wars Day, has inspired gatherings and celebrations of all sorts, including a t-shirt design contest, a LEGO store mosaic, free Star Wars cookies at select Williams-Sonoma stores and special discounts off Star Wars products, as listed on the official Star Wars website.

In Toronto, Canada, fans are gathering for the second annual Intergalactic Star Wars Day at the Toronto Underground Cinema, complete with a trivia game show (based on the original trilogy) and a costume contest. All proceeds will benefit the Sick Kids Foundation.

But Star Wars fans, and the fake Darth Vader Twitter account, aren't the only ones having all the fun on May the Fourth.

A number of celebrities will be blowing birthday candles on Friday, including Will Arnett, former NSYNC member Lance Bass, Saturday Night Live alum Ana Gasteyer and others.

Click through to see which famous faces are celebrating birthdays on May 4, and May the Fourth be with you.