Various RoR properties question for ActiveRecords Models

Okay, I'm working on a program to record registrations for an anime
convention. Right now I have a model for Attendees, a model for
Events, and a model for Payments.

Okay, now I want to have one super event called "AnimeIowa2008" that
every Attendee belongs to. My first problem is that I want to reuse
this every year, so I want each user to have certain flags such as
"2008_sponsor" based on which year they are attending. But I don't
want to fill the database with flags like this, having to create more
each year "2009_sponsor". So what's the best way to save them then,
relative to eac year? Would it be best to, perhaps, create a new model
Venue and give a Venue object to each user with these flags or

Next, the Users are going to -has_and_belongs_to_many Events- because
there are events like "ArtShow" and "ArtistAlley", and each event
belongs_to an event, which is the super event "AnimeIowa2008". Is
there a better way to do this also? Because AnimeIowa2008 doesn't
belong to any other events... so how do I do that?

Would the best solution here be to create a new model, Venue, and make
it has_and_belongs_to_many Attendees? Then how best would I store
information such as the fact the Attendee is attending AnimeIowa2008,
and is a sponsor this year but might not be next year.

I also have to deal with Payments. Right now each one obviously
belongs_to one Attendee, but I might need to make them belong_to
"AnimeIowa2008" whatever type of object that is. That way I can
seperate payments from this year and next year.

I know this is complex... but any suggestions would be helpful :slight_smile:
I'll be up all night, lol.