The first I'll mention is one I wish I could go on. How would you like to go visit the sights in Sparta and Ancient Greece (not, like, time-traveling or anything like that. But just how things look now)? I know it's something I'd like to do. Along with seeing the various sights, you'd also get to hang out with the Red Republic Games fellas and play some Arena Rex.
For those that would like something a bit more recent, historically-speaking, there's the Little Big Horn tour. Go out west and learn about a rather dark spot in American history. Along the way, chat with the guys from Outlaw Miniatures and play some Wild West Exodus.
Both the tours have days and days worth of things happening in them, so be sure to check out the pages for further details and booking information.
Greece Source
Little Big Horn Source