Geeky holidays

March 10 — Mario Day ("Mar10")
March 14 — Pi Day (3.14)
April 5 — First Contact Day, Star Trek (humanity's first encounter with alien life in 2063)
April 26 — Alien Day (the movie occurs on the moon LV-426)
May 4 — Star Wars Day ("May the Fourth be with you")
first Saturday of May — Free Comic Book Day
May 25 — Towel Day (It was first celebrated a few weeks after Douglas Adams' death)
June 28 — Tau Day (6.28; participants are encouraged to eat "twice the pie")
September 8 — Star Trek Day (The very first episode aired on September 8th)