Rails Application variable

It almost seemed that there was no easy way out of putting application scope variables in the database.
But there is a way out:
    if Thread.main[:uuid] == nil
      Thread.main[:uuid]=0
    end
    uid = Thread.main[:uuid] += 1

This code accesses the mail thread of the rails process and puts a variable on it. (the thread is an object and can have key => value sets)
And since rails has only one main thread... its shared with all the threads underneath.

Good Luck