4th of July's coming up and I always think of parades, so maybe there could be a huge one in the Plains. People with groups could advertise themselves by naming their chars the group's name or having the group members follow them. And there could be people with chars colored red, white and blue running everywhere. Maybe the mods would lead it.
For other holidays there might just be a party somewhere, like:
Halloween could be celebrated in Ficho with a bunch of black/orange people. A character contest could be held and the winners get presets and the runners-up maybe a ribbon for the forum.
A Christmas party in the south pole with either players or mods dressed up like santa, elves and reindeer. Whoever was Santa could have people come up and tell them what they wanted for x-mas.
Saint Patrick's Day in Plains with green people wearing the shamrock item and leprechaun chars. Maybe really small, yellow characters supposed to be fairy gold.
I can't think of any others right now, but there's my suggestion. I think it'd be fun, although maybe a drain on the sever. Perhaps the parties would need to be before or after the actual date so people could attend, too.
