Literally Speaking?

This last month I started a Bible study with a few of our high-school guys. All three are seniors and suffering badly from senioritis. They're just dying to get out of school and head off to college. So things have been fun. I figured that we would study hermeneutics in order that they would have a better idea of how to feed themselves spiritually as they go off to college.
Last night we talked about the different genres in Biblical literature. We spent quite a bit of time talking about apocalyptic literature. This genre is probably the most confusing in Scripture because of its frequent use of symbolic imagery. I've always tended to be leery of books like Revelation and Daniel since it seems like they often attract theological nuts.
Lately I've noticed the irony in the modern interpretation of prophetic books. The guys that claim to be taking prophesy "literally" are often the worst when it comes to actually allegorizing the text. They read about locusts in Rev. 9 and begin to talk about Apache helicopters. That just seems silly to me. I think that the major problem with these interpretations is that the interpretor fails to notice that books like Revelation were actually meant to be understood symbolically. Maybe that's the first step to studying this difficult genre.